Keith Jarrett, by public consensus, is equal parts jazz legend and conceited jackass. That is, his stage antics have come to precede him, and he doesn't do much in the way of damage control either.
His undeniable acts of vanity and crassitude have affected the quality of his shows.
Some of these acts of non-discretion include playing in near darkness at Umbria's 40th Anniversary, punishing a crowd of 4,000 for what maybe a handful of audience members did to piss him off.
But it doesn't stop there. San Francisco, 2010: Jarrett interrupts his performance to call out various "coughers" in the audience for their audacity to, while being an involuntary bodily reaction, keep the disruption going.
Carnegie Hall, 2011: Jarrett storms off in a tiff because of coughers and photographers, what is commonplace for most (if not all) audiences there.