Do Take "Note" ... Please Read On -

Recently one of my former students, who is now an accomplished and distinguished performer and educator in Europe, sent me a message containing questions concerning one of my compositions. The reason, of course, was that an artist of his integrity needed to be sure that the notes in question were indeed the notes that I had intended to come into existence.
This kind of questioning is a compliment to the art, as it is a process which is the self-propagating force seeking the truth of the expression that the composer intended; after all, the music left behind cannot be defended by the composer who has passed on.
We see such problems of revisionism in countless compositions left by composers who, before our time, had meager or, indeed, non-existent legal means to defend his intentions.
Just one example:
In the 1985 recording of the Mozart Piano Concerto , K. 488, done in Italy by Horowitz and the conductor Guilini (whom Horowitz had chosen for the task), Horowitz approached Guilini before recording the final movement (this was in the back-room before going out to the studio and the waiting orchestra) and, with the music in hand, said to the conductor that he was aware that Guilini, in a particular measure, which Horowitz pointed out, was done in a particular way, and Horowitz then said "and I do it THIS way."
Well, Guilini was stopped in his tracks, said nothing, and looked for a pregnant second or two at the pianist, who then broke the ice, and said, "tell you what - why don't I do it my way, and you and the orchestra do it your way?" Horowitz then diffidently shrugged his shoulders, upon which both he and Guilini broke out into uproarious laughter.
By the way, in the recording we hear that measure done Horowitz's way, by both the pianist and the orchestra, even though Guilini was an acknowledged Mozart scholar.
And so it goes - you can see this event. It was recorded on DVD, if you can find it. I do have it.