The motions don't have to be different at all. It's simply that the probability that you will stumble on the most efficient motions for certain passages is lower at slower speeds.
I thought we were talking about different motions from slower practice that would not work at a faster speed. I am looking for example of that different motion, don't see it or imagine it.
Most of the time for difficult passages, the most efficient motions that work at high speed are extremely difficult to play in slow motion because they just seem utterly ridiculous and require barely any perceptible effort from the fingers other than brief moments of stability. Your fingers shouldn't tire out at all even for something like 10 no 2, even when you are just starting out.
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That is how I see the process, requiring barely any perceptible effort from the fingers, from slow to faster.
Fingers shouldn't tire at any speed? When the technique is not able to handle a given speed repeatedly, they will tire. Once I work it a little slower, repeatedly for a number of days, then I can play the speed that used to tire, now it does not, even repeatedly.
So you can play at performance speed without working up to it repeatedly without fingers tiring?
Nick