I would go into detail, but I think Herr Beethoven speaks for himself.
I go to the University of St. Thomas, and the music department faculty/students give recitals all through the year. Tonight, the featured event was Dr. James Callahan in his last recital as a faculty member (he's retiring this year), playing "Les Adieux", as well as another Beethoven Sonata (in C minor, Opus 111, I believe). And it was FREE.
Suffice it to say that I will never see those pieces played like that again.
What amazes me is that though Dr. Callahan is shorter and has much smaller hands than I do, he can play like that, and get all over those 88 keys.