A theater actor who constantly forgets or mangles his lines because he can't stand the repetitive and boring activity of rehearsing his roles... A mathematics lecturer who forgets to present simple but important lemmas, and who routinely messes up his blackboard calculations - all because he can't endure the mind-numbing and time-consuming preparations for his assigned courses...
I think that a reasonable person would have a healthy doze of contempt for such sorry "professionals" who willfully disregard the basic responsibilities of their profession. And this contempt would not be diminished by loud assurances that, although such "professionals" screw up the details of Shakespeare and Chekhov (or Gauss and Hilbert), they convey the big picture, the spirit, if you like, of Macbeth or Uncle Vanya (or the Fundamental Theorem of Algebra) better than most.
Yet when it comes to pianists, such unprofessional behavior can be looked upon with tolerance bordering on affection, or even adulation, as witnessed by the axiomatic inclusion of Cortot and Schnabel among the so-called Great Pianists. This is not about wrong or missed notes per se. This is about the easily recognizable difference between wrong notes as neurophysiological accidents (which can happen to any musician) and wrong notes as the predictable consequence of willfully keeping one's technical equipment in the state of sad disrepair.
I would think that, for musicians who choose to make a living as public performers, the latter is simply inexcusable. Rachmaninov toiled at the keyboard for hours each day, playing simple pieces at 1/3rd the normal tempo. Horowitz slaved over tricky passages, repeating them hundreds of times until he got them to sound just right. Rudolf Serkin reportedly spent nearly as much time on practicing as he did on sleeping. But Cortot and Schnabel, it seems, were too busy communing with the spirits of Chopin and Beethoven respectively to waste their valuable time on the drudgery of serious daily practice. And when the time came for these High Priests of music to communicate their masters' revelations by actually playing the piano, the results (as preserved in studio and live recordings) often were as pathetic as a porn flick with an octogenarian male in the lead role.
There is something perverse, or at least hypocritical, in the fact that many of today's fine pianists, who no doubt take their professional responsibilities very seriously, go out of their way to make excuses for Cortot's and Schnabel's abominably unprofessional behavior. When I hear that the technical blunders in Cortot's and Schnabel's recordings are "endearing" (Stephen Hough) or even "fabulous" (Philippe Entremont), I shudder at the thought that the day may come when such affectionate tolerance will be extended to other professions - say, plastic surgery. Perhaps the eloquent Stephen Hough will eventually explain in his blog why it is acceptable to disfigure a composer at the keyboard, but not a patient on the operating table.
In the end, I think my problem is ultimately semantic in nature. I don't respond to Schnabel's playing at all, but I have most of Cortot's recordings, know these recordings very well, and expect to continue listening to them in the future. I certainly agree that there is something very special about Cortot's playing. I just don't think that this something is adequately (or even meaningfully) described by calling Cortot a great pianist.