A friend complained to me the other day that my original post on this topic sort of built up to something, but never quite arrived. He was surely right; but let's be honest, it was getting a little long. You probably didn't even read the whole thing. Anyway, so what's the big deal? Why does it matter if I or anyone can recognize the sound of certain pianists?
First of all, it's totally awesome that, on an instrument with seemingly so little possibility for individuality, it turns out it's still possible. I can recognize as many pianist's playing as I can violinists, or cellists. That obviously would be different if I listened to more violin and cello music, but still, those instruments are played in a completely different manner: more analog, less digital.
Second of all, it's depressing. Given the personalized nature of each pianist's sound, there's no way no one can ever hope to replicate any of them. They can't even replicate each other! So to the extent that our enjoyment of Moravec's Chopin or Gould's Bach depends on their characteristic voicing or articulation, well, that may be lost forever.
Third, and most of all, it's fascinating! And as far as I can tell, not terribly well-studied. As I mentioned, I'm not really sure what's responsible for the effect, whether it is really a note by note phenomenon, or whether it has more to do with phrasing and combinations of notes. But that actually shouldn't be that hard to figure out, right?