The story is not told very clearly in that video, but apparently this was a sort of open dress rehearsal in front of a live audience. Pires definitely looks distressed, but the calm conductor talks her into giving it a go (they'd played the piece before and he knew it was securely in her repertoire) and she apparently came through with flying colors.
So next, Norman Lebrecht posts about how the Berlin Philharmonic intentionally started in on the wrong concerto as a prank in a Prokofiev rehearsal with their concertmaster. Not too surprisingly, the violinist was able to react on a dime and come in on time with Mendelssohn's great tune, though they only play a few bars. I think even I could make it that far into the Mendelssohn concerto, albeit with my patented one-finger L.H. technique.
The Lebrecht post spawned a whole series of commenters retelling other stories about concerto mixups. It's likely that most of these stories are at least partly fabricated, but that doesn't mean they're not good stories! The eminent Martin Bookspan recounts that a pianist expecting to play Beethoven's 5th sat confused waiting for the opening orchestral chord while the orchestra waited for him to begin the piano intro to Beethoven's 4th. Bookspan couldn't recall who the pianist was, which made me wonder if his story had descended from this one described by Gary Graffman regarding Rachmaninoff's second concerto (which begins with piano chords) and the "Paganini Rhapsody" (which begins with violins):
"Years ago in Los Angeles I was scheduled to perform the Piano Concerto No 2. Unfortunately, my manager had told me it was the Variations. Having just arrived in the city, I dashed to the rehearsal in the morning, took my place, and waited for the downbeat of the conductor. He turned around expectantly, stared at me quizzically, and waited. I waited. He waited. I waited. Where were the violins stating the familiar theme? Finally, in a burst of excitement and confusion we untangled the misunderstanding. ‘If you are set to play the Variations we can change our program,’ the conductor soothed. ‘Oh no, it really doesn’t matter to me at all,’ I stubbornly countered, ‘I know them both equally well.’ A few hours later we performed the Concerto.”I remembered this story because I read it at least 100 times on the back of this much-loved LP that belonged to my parents. (You can read the liner notes here.) I could make the case that this is the single most important record in my own musical life, as it's the first music I really fell in love with (first the rhapsody, and then some time later when I "discovered" the other side), so perhaps it can be blamed for all the words I'm spilling here.
So there's that. Both I and another commenter chimed in with an old story about a conductor surprising a soloist by giving the orchestral downbeat too soon in the Schumann concerto (in which the pianist comes in right after) with the pianist getting revenge by starting the 2nd movement before the conductor was ready. I also like the version in which the unprepared pianist manages the cascade of Schumann chords and then promptly throws up. (My wife just told me her youth orchestra conductor used to tell that version of the story as well.)
But my favorite commenter story was this:
....In the cello circles the famous Wierzbiłłowicz, a heavy drinker himself, asked the conductor: what key we are in? A minor, came the reply. Unfortunately, it was Schumann, not Saint-Saens.
Here's how Schumann's cello concerto begins:
Here's how Saint-Saëns' begins:
And here's how I'd like to think Mr. Wierzbiłłowicz's apocryphal performance might've sounded, with the soloist suddenly sobering up 10 seconds or so in:
You know what? It kinda works...