Usually I have to perfect a piece at Allegro and then slowly get it to Presto starting with single beats, and then merging every 2 groups of beats until I can play the whole piece Presto nonstop.
Well I was practicing Chopin's Grande Valse Brilliante for the first time today. I tried practicing it years before. I was in my second year of piano and I figured "I can do Chopin now because I am a fast learner". Well that turned against me and I wasn't able to do it. I clearly needed to learn a technique for fast piano playing.
About a year later and I am able to play notes very fast. But I still did not go after Presto pieces for years. It seemed intimidating. Finally I plucked up the courage and practiced the Solfeggio in C minor. That is when I realized the speed up to Presto had to be done differently than the previous speed up to Allegro.
And now today I am able to play the right hand of Grande Valse Brilliante for the most part correct at speed with only a few wrong note errors that are inevitably going to happen when you play super fast. It just exhausts my hand though to play that fast. I can feel the burn. The same thing happens when I do a continuous Alberti bass at Allegro.
But why am I able to play the right hand at Presto with no previous practice of that piece? Does it have to do with the fact that I have listened to Grande Valse Brilliante a lot and thus the notes and tempo have been ingrained into my memory and that I am playing my right hand that fast only because I have great memory of things I listen to?
My left hand isn't up to speed yet. With all those leaps I have to slow down my left hand for accuracy.