What's the difference: practice vs performance?

[m1469]

I am wanting to give this subject some deeper thought and decided to ask you all what you think...

in essence, 'what is the difference(s) between  performance and practice?'

Webster defines practice as:

"5. the action or process of performing or doing something"

Perform as...

"1. to carry out; execute; do
 2. to go through or execute in the proper, customary,   or established manner"

and...

'are we to be held more responsible in one or the other?'

'is more skill required in one vs the other?'


My conclusions thus far:

1.  Performance is not an isolated experience

2.  Performance is part of pracitce

3.  They are essentially the same

4.  We should be held equally responsible in both

5.  Skill is required equally in each


I would really like to learn what others think...


Thanks,

m1469

[Max]

Practise - to play with the intention of improving

Perform - to play with the intention of entertaining others

(in their most basic forms)

[bernhard]

Webster definition is highly arguable. And keep in mind that there are two very different meanings to the word practice:

You can “practice” a profession – like a Doctor (=general practitioner), which means that you re actually doing the job, or you can “practice” the piano – in order to one day be able to do the job. I suspect that the Webster is defining the first instance, not the second.

The Oxford Dictionary is far more enlightening:

Practice (n): 1. The actual application or use of a plan or method as opposed to the theories relating to it. 2. the customary or expected procedure or way of doing something 3. the practising of a profession – the business or premises of a doctor or lawyer. 4. the action or process of practising.

Practise (v) (US practice) 1. perform (an activity) or exercise (a skill) repeatedly or regularly in order to acquire, maintain or improve proficiency on it. 2. carry out or perform (an activity or custom) habitually or regularly. 3. be engaged in (a particular profession) 4. Observe the teaching and rules of (a particular religion). 5. archaic – scheme or plot for an evil purpose.

Performance (n) 1. an act of performing a play, concert or other form of entertainment 2. A person’s rendering of a dramatic role, song or piece of music. 3. (informal) a display of exaggerated  behaviour; an elaborate fuss. 4. The action or process of performing a task or finction. 5. the capabilities of a machine or product 6. the extent to which an investment is profitable 7. (linguistic) an individual’s actual use of a language, including hesitations and errors. Often contrasted with competence.

'are we to be held more responsible in one or the other?'

I am not sure what is meant here. What has responsibility to do with it, except in a trivial sense?

'is more skill required in one vs the other?'

You need skills in both, but they are of a very different sort. Intriguingly, you will acquire the skill to perform through practice, but the skills needed for practice cannot be obtained or derived from performance skills.

My conclusions thus far:

1.  Performance is not an isolated experience

It depends if you had more than one performance

2.  Performance is part of pracitce

Performance is the goal of practice.

3.      They are essentially the same

They are essentially and functionallydifferent.

4.  We should be held equally responsible in both

I would like more details on this “responsibility” issue (e.g., what is the alternative?)

4.      Skill is required equally in each

Yes, skill is required in both, but the skills are of a very different nature.

Here are some further thoughts of mine on this subject:

Practice is the process by which you learn/perfect something so that you can perform it.

Practice implies improvement – you can even go as far as I go and say that practice means improvement. If you spend 10 hours a day playing the piano and at the end you have not improved you have not practised. You have done ten hours of piano activity for sure, but you cannot call it practise. Performance on the other hand does not imply improvement (although you may well get it as a side-effect). It implies that you have reached a point of perfection/improvement that you can and should share your art with others.

Practice is private, performance is public.

You practise in order to perform, but you do not perform in order to practise.

Practise leads to performance, but performance does not lead to practise.

Performance will give you new ideas to practise, but practice may or may not give you new ideas to perform.

You can and should practise performance, but you cannot and you should not perform practise.

Practice is the process, performance is the product.

Practice does not make perfect. Perfect practice makes perfect. The only activity where perfect practice does not make perfect is Russian Roulette.

Best wishes,
Bernhard.

[Sketchee]

Thinking about the activity of practice compared to the activity of performance, I think if you're practicing correctly and efficiently it will be very different than a performance. If your idea of practice is solely to play through a piece entirely without stopping regardless of errors, then that would be more like a performance.  Hopefully though, you don't just do this.  It may be helpful to run through as if performing and take note of problem areas that you'd practice in more detail afterward.  Playing hands seperate, at a slow tempo, small sections, etc ... all of those things are part of practice or at least can be.

[m1469]

By responsibility, I am talking about focus, attention to detail and expectation, among other things.  Although I am quite certain that you, Bernhard, are probably at a point where you only see the worth in practicing with the utmost attention, and to use my previous choice of wording, responsibility,  I am not convinced that everybody who performs feels individually responsible in this way every time they sit down to practice.  Does this explain to you what I mean?

As far as skills are concerned... I am talking primarily about what many people consider to be the "skill" of playing the piano, in general.  Many people think that the better an individual is at practice, the better they are at performing.  Or, more ignorantly, the better one is at performing, the better one is at practice.   As I stated above, I believe the same expectations must be applied to both in order for them to serve eachother.

I do not quite understand what you mean when you say that one "will gain the skills needed to perform through pracitce, but that the skills needed to pracitce cannot be obtained or derived through performance skills."  Could you expand?  What exactly do you mean by performance skills?

1.  I am implying that the performance is only a piece of the puzzle, and is therefore not achievable in and of itself.  It must be arrived at through pracitce and is in my mind, therefore, a piece of a larger picture.  It is fully inclusive of a lifetime preceeding it, and has a lasting influence, in some way, over that which comes after.

2.  One can pracitce without a goal of performance, but cannot perform without the goal of practice.

3.  Look below...

Perhaps I am very ignorant here, but shouldn't one always strive to improve through performance?  Or, more directly, learn something which can in turn be useful in future pracitce and performance?  

It may be that I am simply at a certain stage in the game, but every time I perform, it is with the primary intention of improving in some way, and learning something.  To an extent, I could care less how my best efforts are received by others, so my primary goal is not that of entertainment.  I also never expect to ever be "finished" with or forever perfect any peice of music I would ever program.  Even if I believed it to be possible, in 20 years I will bet my life savings (sorry, it's not much) that I will be playing it much differently.  And, unless I have lived in a hole without a piano or the mental capacity to think of one, it will be improved.

Always, a performance will not go over without any hitch, and somebody will walk away dissatisfied.

In my mind and at this point anyway, each performance is a pracitce for the next one.  I do not think that this is the same thing that you mean by saying that "you cannot and should not perform practice."  Correct me if I am wrong.

Also, if performance truly is the product of practice, it seems that this assumes there to be no further ramifications from performance.  Is this right?  And, shouldn't the product of practice be the perfection itself?  Perhaps this is what you mean by performance.  (wow, too many "P" words).

I appreciate your thoughts.  

Also, I appreciate your conclusions about practice and improvement.

Have never tried Russian Roulette....  :-/

Thanks,

m1469

[namui]

Objective of practice is different from performance. Mechanically, the two can be very similar (playing piano).

It is possible to use the mind-set for public performance in private practice if one believes that the intensity of performing will raise the playing skills. And it is possible to treat performance as practice if one believes that focusing on gaining experience from performance helps reduce the tension of performing to the public.

Anyway, there are many other aspects that are not intersected between the two activities. For example, practice techniques may include divide-and-conquer, rhythm variation, slow practice, etc. all are targeted towards efficient development of each specific skill. Performance may include full focus on the musical communication, and any unexpected mistakes should be neglected right away (or at least until the performance finishes).

My 2 cents ...

namui

[bernhard]

m1469 wrote:

I do not quite understand what you mean when you say that one "will gain the skills needed to perform through pracitce, but that the skills needed to pracitce cannot be obtained or derived through performance skills."  Could you expand?  What exactly do you mean by performance skills?

Skills needed for practice include the knowledge and ability to execute practice tricks. But they also include the ability to focus and concentrate, the ability to repeat something endless times, the ability to analyse and study a score, the skills to deconstruct a piece and reconstruct it, the ability to listen critically to other performers (either live or in recordings). All of these will be essential to develop your skill at playing the piano which is the bottom line if you want to perform. If you cannot play the piano, how can you perform?

However the converse is not true. Performance skills will not add to your practice skills. In fact you can learn to practise in order to play the piano to a high standard of excellence without ever performing (many amateur players only play for their own delectation). Not performing will not in any way interfere with your practice/playing.

Performance skills (I am sure there are more – these are the ones that come to mind):

1.      Of course the skill of playing the piano (which will be acquired through practice and the exercise of the several practice skills).

2.      Dealing with an audience. This encompasses everything you do once in a stage, from entering the stage to bowing to leaving the stage. You can tell straightaway the seasoned performers from the green ones by their degree of self-consciousness on stage. Naturally the “stage” is here taken in its widest meaning and includes your living room when you are playing for friends. This kind of performance skill has nothing to do with piano practice. It will not inform your piano practice, and yet it must be practised. I suggest to my students that they learn magic tricks and perform them to develop the skill of appearing naturally when fooling an audience. Playing the piano in public is – in a certain level – an illusion that you must sell your audience, and as such has much in common with magic. Being at ease in front of an audience is not something we are born with (even though people often talk of “natural performers”). It must be learnt and practised, and has nothing to do with piano practice per se.

3.      Dress sense. Superficial as this may seem, it will have an impact on your performance and must be gauged appropriately according to your audience and their expectations.

4.      If you become really famous, your whole life can become a performance as you are pursued by paparazzi and so on. Dealing with the public and with the press at this level is also a performance skill – although classical pianists tend to suffer less from it than pop musicians and actors. Success and fame can wreck you if you do not have the skills to deal with it. Again this will not inform your piano practice in any way whatsoever.

5.      Part of performance skills is to be able to adapt to different pianos and different hall acoustics. This must be practised – but can only be practised through performing indifferent pianos and on different halls. This sort of skill cannot obviously be done on your piano at your home.

Perhaps I am very ignorant here, but shouldn't one always strive to improve through performance?  Or, more directly, learn something which can in turn be useful in future pracitce and performance?  

It may be that I am simply at a certain stage in the game, but every time I perform, it is with the primary intention of improving in some way, and learning something.  To an extent, I could care less how my best efforts are received by others, so my primary goal is not that of entertainment.  I also never expect to ever be "finished" with or forever perfect any peice of music I would ever program.  Even if I believed it to be possible, in 20 years I will bet my life savings (sorry, it's not much) that I will be playing it much differently.  And, unless I have lived in a hole without a piano or the mental capacity to think of one, it will be improved.

Always, a performance will not go over without any hitch, and somebody will walk away dissatisfied.

In my mind and at this point anyway, each performance is a pracitce for the next one.  I do not think that this is the same thing that you mean by saying that "you cannot and should not perform practice."  Correct me if I am wrong.

Also, if performance truly is the product of practice, it seems that this assumes there to be no further ramifications from performance.  Is this right?  And, shouldn't the product of practice be the perfection itself?  Perhaps this is what you mean by performance.  (wow, too many "P" words).

Consider a card trick. A really superlative card trick that will leave people completely gobsmacked and believing your supernatural powers will need to be practised for (sometimes) years, before you can actually perform it.

What is the point of performing it? To leave people completely gobsmacked and believing your supernatural powers! Of course there may be other reasons: Money, fame, impressing the girls. However the true reason anyone takes up magic tricks is a deep love of fooling people. Quite sick I know. But it is the truth. Specially fooling the scientific types who think they can crack any trick. They are a source of immitigable pleasure, partly because they don’t even come closer.

It may seem I am digressing, but I am not really. The point here is that no one would be investing the time and effort to practise a magic trick unless they intend to fool (or amaze, if you want to be kind) someone with it. So performance cannot be avoided. At the same time you are not going to fool anyone with your magic trick unless you have practised it to perfection. So the (successful) performance must necessarily assume previous practice.

If you botch it (and doing magic for children is the hardest, trust me), of course your botched performance can teach you a lot and inform you that your practice was not enough, or that it was wrongly done. But this is not the usual. You do not expect to botch your performance so that you can learn from it. Learning from performance cannot be the final goal of performing. A philosophy like that is simply a way to save something from a botched performance: “All right, I really flunked it, but hey, let us look to the bright side! At least I learned what not to do!”. (It is a good philosophy).

Hence the performer’s axiom (be it magic or piano): Never perform something you are still practising (because you will botch it). You are not going to fool anyone if your magic trick is still in the practise stage. And surely you should never practise your magic tricks in public: it will give away the secret.

Now of course, as you perform your trick to different audiences, you may have to adapt it, you may get new ideas and variations, but you should practise these new ideas and variations privately first, although some people will improvise on the spot and get away with it.

Many card tricks are based on a move called the “double lift” where you show a card to the audience, but instead of lifting one card from the deck, you lift two. In order for this sly move to pass unnoticed you need a special way of lifting the two cards (in fact there are several – but every magician has his favourite) and showing them as if it was one. Making this slightly awkward movement to appear completely natural is essential for the success of the tricks that use it. Mixing up practice and performance as you seem to be suggesting can result in two consequences that you want to avoid at any cost:

1.      You have not practised enough, so your double lift is easily detected (for it will be awkward) and you will fool no one.
2.      You practised enough, and your double lift is fine, but you insist on practising it in front of the audience. It is obvious that no one will be fooled by your trick even if the double lift itself is undetectable.

Hence: only perform when you have achieve mastery through practice, and when performing, do not practise.

When I say you should not perform practice it is in the sense above. Would you sit at the piano in front of an audience and break down the piece into manageable chunks and repeat them until mastered? Would you do hands separate first? If you are into Hanon would you do five minutes of warmup at the stage? Somehow I doubt it.

Having said all that, I agree with several things you say. Here are some more thoughts:

Perhaps I am very ignorant here, but shouldn't one always strive to improve through performance?  Or, more directly, learn something which can in turn be useful in future pracitce and performance?

Yes, you should always strive to improve, but public performance is not the venue to do it.  The venue is of course private practice. In fact you hit the nail on the head on your next sentence: performance can show you the direction of your future practice. But this should not be the ultimate purpose of performance, just a side benefit.

Also, if performance truly is the product of practice, it seems that this assumes there to be no further ramifications from performance.  Is this right?  And, shouldn't the product of practice be the perfection itself?  Perhaps this is what you mean by performance.  (wow, too many "P" words).

Perfection is unattainable (which is exactly what makes it such a worthwhile goal). So perfection is not the product of practice, but rather its unattainable goal. Through performing you show us (and yourself) how close your practice got you to that goal.

It may be that I am simply at a certain stage in the game, but every time I perform, it is with the primary intention of improving in some way, and learning something.  To an extent, I could care less how my best efforts are received by others, so my primary goal is not that of entertainment.  I also never expect to ever be "finished" with or forever perfect any peice of music I would ever program.  Even if I believed it to be possible, in 20 years I will bet my life savings (sorry, it's not much) that I will be playing it much differently.  And, unless I have lived in a hole without a piano or the mental capacity to think of one, it will be improved.

Of course you can do whatever you want, but I don’t think that one’s primary intention in performing should be improving. This should be the primary intention of practising. Why do I say that? Because if your primary intention when performing is to improve, how exactly are you going to go about it? It creates an impossible situation. Are you going to stop at every bar and repeat it several times? Are you going to investigate new fingerings right there on the performance? The extreme nature of these examples should show that improving cannot be the primary intention. Although I agree with you that you will improve through performing – but it is a side benefit, something to keep an eye on, but not the main thurst and drive of your desire to perform. So why should you – or anyone – for that matter – perform? To entertain the audience? To please oneself? To do justice to the composer?

I have said once that for successful teaching to occur three conditions must be present: a student willing to learn, a teacher willing to teach and an environment conducive to teaching. If these three conditions occur learning will take place. If any of these conditions is missing there will no learning and no teaching.

I find this to be true of every manifestation in the Universe (how about that for sweeping generalisations? ): you always need three forces at work. If one is not there, whatever will not take place.

So as far as performance goes, for it to be successful three things must be in place: You must be satisfied that you did your best. The audience must be entertained (using this word in a superior sense), and the music must come through. So the main direction for performance will always depend on these three forces: the music, the audience and the performer. No one is more important than the other. The three are equally necessary. If anyone is missing there will be no performance (or it will be unsuccessful). But the individual contribution of each force may vary: in certain performances the performer will outshine the music and the audience, in others the music will prevail, and in others the audience. If you are familiar with vectorial analysis, you will know that the resulting force of three vectors will be determined by the direction and intensity of the individual vectors. So it is here. The individual contribution of audience performer and music will ultimately (and mathematically) determine the direction and intensity of the performance.

Best wishes,
Bernhard.

[m1469]

Okay, I realize that I must have flaws in my concepts here, but now I have questions... and stuff...


1.  A person will never please everyone and sometimes nobody, not even themselves.  It's the hard reality of a human sense of existence (I know that you already know this).  So, why should my goal in any avenue of life, especially in that of a performance situation (where vulnerability is at its most for me) be about trying to do so?

In the case of your card trick, there are those who will be completely amazed.  They don't want to know the trick, they simply enjoy the amazement itself and more than not, they simply want to forever believe that there is some kind of true magic and mystery out there that can amaze them (this category makes up a great deal of many audiences).  
 There are also those who see that a trick has been performed, and that there are large numbers of people who are completely amazed, and they want to learn how to do the same thing (probably a few in every audience).  Then, there are those who will always suspect and on some level know, that what appears as  magic is actually, simply and fully an illusion.  And, although they do not know the trick to it, nor do they figure it out, they are never convinced of true magic.  These people attend such events when they feel the magic will seem the most real, and pride themselves in walking away still unconvinced and mostly dissatisfied, over and over again.

Who wins?  nobody is really ever truly under the spell of the magic itself, because, with all due respect, it doesn't exist.  It is only an illusion.  Even those who feel completely amazed and awe-struck, are not necessarily in that state of mind for the correct reasons, and are actually under the spell of illusion, not magic.  There seems no way around this to me.

So it seems to me, that one who performs "tricks", knowingly does so with the intention of putting those they can under the spell of illusion, not magic.  People who perform "tricks" practice hoping to get better at the illusion so as to fool even the most questioning minds.  But who wins?  What is the thing that anybody actually walks away with?


2.  It has been my suspicion of a few years now that it is actually impossible to ever truly master the instrument, along with a truly genius piece of music; mastery meaning to me, that there is nothing more to be learned.  I am under the impression at present, that there will always be more to learn.  With this being said, I don't want to enter into any performance situation, in which the idea is to share, ultimately trying to fool people into thinking that I have learned it all.  I would much rather have people walking away having a deeper and truer insight into what is really taking place, and even though it is not perfect, because it cannot be, they are walking away with something true and honest.  In this case, I have really shared something.  Please understand that i don't look at this as an excuse to purposely leave in blemishes and imperfections, I believe in the uttmost preparation.  My only thought is that it will never reach perfection and will therefore, always have room for improvement.

Please, if you have further insight on this point of view, or see a need for correction, share!  I am happy to be convinced into growing out of views and thoughts that need growing out of.

Perhaps I have been wrong.  I have thought that somehow and in some way that truth and honesty would ultimately be best.   Should one who performs be in the business of illusion?  I am truly asking.  I have never thought of this as my job in performing, but I see that this is the very question I have been mulling over for a while now.  Should a performer be satisfied if they have simply convinced the audience of their magic powers even though it doesn't actually exist?  Knowing this would also change my concept of practice as well.

Thanks for helpful thoughts,

m1469

[m1469]

Okay, I realize that I am not saying everything that I am trying to say.  Let me see if I can explain it better...

When I am talking about performance and practice, I am speaking about principels of living.  Learning is a principle of my life.  Everything I do, I want to learn.  I am so curious about Life, that I deeply and truly want to know enough to be able to explain something true to people.  I also believe that there is a Truth.  Frankly, this is what I most care about.

When I was quite a bit younger, I was very obsessed with wanting to be beautiful.  I went to great lengths to try to discover what beauty is, how to get it, how to convince others that I have it.  I would read about it, and then try to simulate what I read.  I would experiment with eye-shadows and mascaras, eye-liners and lip sticks... and of course foundations, concealers and powders.  (These latter make-ups are the most mentally harmful in my mind because one is striving to cover-up blemishes, and ultimately one's entire face.)  Perhaps a great many people would consider this kind of reading and experimenting and striving to perfect, "practice."  But, this is not at all the type of pracitice that I am speaking about.

First of all, beauty itself never lay in those products.  No matter how good I got at using them, something essetial was always missing and I felt very naked without them.  I gradually realized that my answers to finding true beauty could not lay within the attitude that says these products provide it.  Looking back, I see that I was not really practicing true beauty at all, but rather, I was practicing and therefore displaying (or performing, if you will) the attitude that thinks beauty is lacking.

Now, beauty is to me, what most people would see as a philosophy.  For me, though, I have profoundly deep thoughts relating to it.  The point is, that until I started performing this philosophy, I was not practicing it, and until I practiced it, I was not performing it.  Again, I am speaking about principles here.  For me, there is no separation between beauty as practice, and beauty as performance, beauty itself is to me, a principle which involves both as a unit.

One of the most helpful peices to this puzzle for me was waking up from the thought that says I have to please others.  It is simply and extraordinarily impossible.  I have some very individual features that would probably attract some and repel others.  So, my lesson was further in that beauty did not lay in the features themselves, nor did it lay in their acceptance from others, but much more deeply than that.  It lay in the simultaneous practice and performance of the principle of beauty itself (with some specific understanding).

This is very broad, perhaps too broad.  But, because there are certain things which are principles of life for me, they extend into every aspect of my living.  And, with music I feel the necessity to let what I consider to be true beauty, again a philosophy of sorts, be of the uttmost importance.  From this standpoint, there is no difference to me between performance and practice, but I realize there are pracitcal needs which are only hinted at by this statement.

The motions one takes to practice beauty cannot be different simply because there are more than just your own set of ears listening.  I realize that in preparation for a "performance" one takes different turns.  But the stroke that displays beauty, has been born of the principle that involves for me, both practice and performance in a very broad sense of these words.  The principle is the same and must be, in both human circumstances called "performance" and "practice".

I think that it is like what you, Bernhard, were talking about when you said "practice doesn't make perfect, but perfect practice makes perfect."  Well, perfect practice I can only assume, means to you, the practicing of something that is already correct, and which is already being performed.  

Furthermore, nobody can take inability and make it able.  Ability is itself ableness.  We are not truly practicing ability until we are performing ability.

Also, one of my biggest realizations about beauty, is that I did not just want people to be tricked into thinking that I am beautiful.  I want to be, actually beautiful.  For me at this point in my life, this has shown itself in the form of me rarely using makeup.  And, I never try to cover blemishes, primarily because if I go around thinking I have something to hide, I am not practicing what I know to be my highest sense of beauty, and I am therefore, not performing it.  I also no longer feel the need to try to convince people that I am beautiful.   I just try to live it!

As with music.  The only thing is, at any given point and in any given circumstance, I can only do as well as my highest thoughts allow me.  So, in a very real way, my best performance is always that of practice.

And, just as I contrarily-to-the-world believe that my sense of beauty will grow through the years as my understanding of its principle increases, I also believe that my ability to demonstrate music will increase as I better perform and practice.  In essence, never am I at a final or perfected or mastered state of existence, either in "performance" or "practice".  And I don't want to waste energy trying to convince people that I am.  This is not my job.  Just as for me, being beautiful is not about trying to convince people that I am so.

Okay, that's it for now.

Bye-bye,

m1469

[CC]

Your question is very important to me because it impacts on the question: I can play quite nicely when practicing, but when there is an audience, I get nervous and can't play as well -- why?

I believe that, from a psychological point of view practice and performance are as different as nite and day, and when you don't understand that, you will never know what will happen when you try to perform -- which makes disaster highly likely.

Simply put (as others have explained, its much more complicated) during practice, your mind says "learn something", whereas during a performance, it says "make music". Note that there is very little in common between these two views, and can explain why you might play well during practice, but can't perform at all. Moreover, performance is difficult to practice because it is generally not possible to pretend and succeed in fooling your own brain. Therefore, even if you are pretending to perform and playing the same sonata during practice, a mistake is just something you will need to work on later, whereas during a performance, the same mistake evokes a terrible emotional disappointment. Of course, stage fright is a related, but different issue, so let's not go into that for now.

Now that we know that practice and performance are different, how can we learn to perform?  I think this is the crux of the matter.

The first is to understand the differences: psychological, environmental, and preparatory procedures.

The second is to find ways to fool ourselves, or to simulate a performance as closely as possible.  There are many ways, such as playing cold, or just pretending to perform when you get tired of practicing, just "perform" a piece from repertoire, or recording your "performance" (you can't stop if you make mistake, you can play once only no matter what), and a third is to start slowly -- don't perform a full formal recital, but start with playing parts of easy pieces for friends, etc., so you can just stop playing or start talking if you make a mistake and cover it up. Preparatory procedures are extremely important, especially playing moderately slowly before a performance, and not over-practicing on the day of performance.  It is also very important to just sit down and play it every time you see a piano anywhere.  Your credo here should be :  a true musician can play any piano at any time at any place.

These examples show that the key is in understanding the difference between a practice and a performance -- when they can be accurately defined, you can use your imagination to find ways to solve the problem. Of course, there is nothing like actually performing to practice performing, and the general rule: "you can't perform a piece until you have performed it three times" seems to be generally valid.  Unfortunately, many recitals conducted by teachers and competitions don't help much -- they often do more psychological harm by teaching the students how to get nervous more than how to perform, because these concepts are not understood.