That's what it is that you rehearse - the making of music, not the playing of notes as abstractions.
“I was always playing the Hammond Organ back to front even during the days of the Nice, going back to 1968. Really what I was doing there, was choosing notes at random and trying to make some sense of them, improvising back to front.”
“I really hate the duties of being a celebrity, like getting dressed up for the red carpet.”