I'll be glad to...there were two main problems in this piece: the first one was that EP is no pianist, so the writing is extremely uncomfortable. The second is the sheer speed: it's supposed to feel like a machine, so the "not human-controlled" aspect is important, I think. But it poses a problem since the score is way to complicated to not have your mind racing, trying to be in charge.
The first decision to make is if you want to play this by heart. And that is quasi impossible, I have done that at home, but I still use the score in concert. However, and this is really important: even if you will use the score, THE FIRST THING to do is to memorize the piece. Take line by line, phrase by phrase, and before you learn it AT ALL technically you put the material in your brain. This will help you enormously later on. Take for example one page for one day, and at the end of the day your goal is to be able to play that page through, very slowly, but without score. When you play the piece in tempo later, you are not really reading the score, the score is just "filling in" what you already know. To me, it made the difference of being able to play it very fast or not. (EP's metronome markings are VERY fast).
The unpianistical writing has a few different sides to it. One is that in something like the finale of Hammarklavier, or the cadenza of the first mov. of Proko 2, the hands and arms are in motion all the time. Take the beginning of Mecanisme, first there are repeted chords when you just cannot move your arms, and all of a sudden you have to move extremely quickly in chords up and down, back to repeated chords etc etc. We don't think so often how awkward "non-motion" things are at the piano, and I really don't think EP thought of it either, haha. So you have to work out some way to be pretty conscious about if you want to play fast repeated chords with wrists, forearm or actually mostly with fingers.
Another thing is the middle section, which EP called A Bach invention gone mad. There are slurs, staccatos and other articulations all the time. Plus, the meter is completely different in left and right hand, with "downbeats" coming at very different places in left and right all the time. Here EP actually complained that he didn't expect this place to sound too dry, like he had heard it many times. The trick there is to have an extremely fast "switch" in your hand: when it's staccato, the hand is superalert and more quick, and when you start the slurred notes, the hand has to be switched to a much more relaxed state, and this goes on and on in a superquick tempo, mostly in piano, with very short slurs, and they come at completely different spots in left and right...
There was no way I could do this without "programming" my hands, and I think the name of the piece permits that. I worked in small parts, starting with memorizing (including, of course, memorizing the articulation, too) and then going VERY slow, with metronome, and speed it up a little more and more. I noticed that this piece was the first that even if I could play it in tempo, I had no real comtrol, and that's how it should be...and that is why it's so imperative to memorize it in the beginning. You feel like you're on a rollercoaster, actually: it looks really impossible, but even though you scream, you know that nothing will happen, because it's built to not break...well, the "built not to break" is the memorizing at the beginning.
Hope this is at least a little clear!
All best to you,
Per
www.myspace.com/pertengstrand
Topic: Hardest piece I've ever played