That's not just a jazz perspective! Here's an extract from the classic, out-of-print, and very hard to find, "Playing the Piano for Pleasure" by Charles Cooke. (If you are curious about the book, ask me to post some of the comments pianists like Rubenstein and Arrau made about this book

. I give you a rather lengthy quote to give a feeling of his charming personality:
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"Surgeons tell us that a broken arm or leg, if it is correctly set, becomes strongest at the point of the fracture.
I like to imagine an analogy between this and the process I am about to describe, a process that is fundamental in the task we have set ourselves.
Recognition of the value of working especially hard on difficult passages is no new idea in piano teaching... But my approach to this factor in piano study is perhaps unique. For I don't approach it with emphasis, or stress, or insistence, I approach it with fanaticism, with mania!
I am now looking you straight in the eye and I am speaking slowly and rather loudly:
I believe in marking off, in every piece we study, all passages that we find especially difficult, and then practicing these passages patiently, concentratedly, intelligentyl, relentlessly - until we have battered them down, knockwed them out, surmounted them, dominated them, conquered them - until we have transformed them, thoroughly and permanently, from the weakest into the strongest passages in the piece."
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He then enumerates the advantage of this fanatic approach, mentioning how it helps with overall technique, the technique of memorization ("No difficult passage can be mastered without, early in the operation, memorizing it."), and makes the rest of the piece easier (like Bernhard's dictum "a piece is only as hard as its hardest passage.") Then he describes how to be especially aware and find "fractures," which is not so important here, and finally various ways to correct them.
Memorization is always first: "...dispense with the notes altogether, drop your eyes permanently to the keyboard, and settle down to setting that fracture." "...inserting frequent repetitions with the eyes closed." Several suggestions for practicing are given, which are probably familiar for the serious piano student, including altering dynamics, adjusting the dynamic balance between the two hands, hands alone practice, practicing in different tempos, including much faster than the performance tempo, making a tape recording, etc. It lacks nothing in thoroughness.
Interestingly, it doesn't include a consideration of the physique, but has the inspiring idea that difficulties can be solved without worrying about a physical answer. The only time he considers that something might not be possible is "if you ever do find yourself marking off a fracture which runs to pages rather than measures, the probability is that the piece as a whole is beyond your ability and should be laid aside to take up later."
I love this book because he promotes with such great enthusiasm the idea that just through musical study of a passage, taking it apart, putting it together, inspecting it, retooling it, problems can be solved, without the merest hint of the baffling language that goes into the preachers of the physical, language which hardly ever matches up with our admittedly skewered kinaesthetic sense. By this philosophy, passages you encounter but don't know how to solve immediately don't require a conscious change in phyiscal approach, but only the answering of the question: of what music is this passage made? and then, repetition of those elements until they become supremely familiar.
Since nobody can predict the future, the only thing that will tell you if you are struggling too hard to achieve something that cannot be achieved, is if you lose the will to achieve it. Or if you approach it with expectations, such as, I should be able to learn this in one day.
Walter Ramsey