From the 10,000 word post:
"If the elephant was described first as purple, it must remain purple forevermore. If your original purpose was to make the elephant green, you should have remembered to describe the greenness of the elephant accurately from the outset ... If the elephant's greenness was somehow incredibly important to the backstory behind the elephant, then change the backstory that hasn't yet been told to the players."
You must try to be consistent. If you are not consistent, cover it up.
There are those who would balk at that advice. Deception is the same as lying, and lying is - in the opinions of some - NEVER an acceptable strategy in presenting the game to your players. Your players deserve respect; if you make an error, it is beholden onto you to admit your error, set it right, apologize if need be, and move on. There is no justification, ever, for lying to your players.
About fourteen years ago I was performing a play in Edmonton for the Fringe Festival; it was a fairly large cast, twenty-six in all, and for much of the play we were all on stage at the same time. The director had worked out a pretty good gimmick. The scene was a bar. There were seven tables and seven stories; and as the 'server' came around to drop drinks off at a particular table, the spot would come up and the scene at that table would commence; she'd serve the next table just as the scene ended, the spot would change and the play continued.
This required some pretty precise blocking, along with a very precise technical schedule; we worked like hell on getting the timing right on every scene - not easy with seven tables and twenty actors on stage.
There was an actress I worked with at my table whose father died while we were in Edmonton. She was devastated; she was not sure if she wanted to continue through the rest of the week, or if she could continue. But we were in the second largest venue of the Fringe (which cost us a lot) and the reviews were fair; it was an opportunity for all of us. She had no back-up, so it was going to be a furious mess if she left. She decided to stay - and the first performance after left her a wreck. She got through it all right and thankfully we had a 36-hour break before our next performance. She rushed back to Calgary to be with her family.
When she made it back, she was bone-tired. I don't know if she got any sleep before we went on. And in the middle of our third scene, she froze up.
Shit, anyone who performs can tell you a dozen stories like this. People forget their lines. I messed up in the middle of a performance of Chekhov in High School and filled the time by walking back and forth across the entire stage while the stage manager (my girlfriend) mouthed words at me. It happens and you do your best. In this case, the other fellow at the table and I both got what was going on at the same time - and we staged an impromptu argument that lasted just long enough to get us past her lines, give the cue to the techies and the server. It was a complete fabrication. It was a LIE. What should we have done - stopped and told the audience why we'd spontaneously changed a play they had never seen?
Hell no! You do what makes the play work. You fake, steal, break things, stage fistfights - whatever it takes, so long as eventually you get the play back on track and the audience never gets bored. AND you don't tell them that's not how the play was meant to go.
I had a friend who was an electrical engineer who did stage work for independent theatre in Toronto. He was working tech on a play he was producing, which included this massive electrical apparatus in which Nietzsche - a character in the play - was supposed to step inside for his 'transformation' into Superman (Nietzsche's, not Hollywood's). Well, came time for the scene and it didn't work. At all. Damned electricals.
The actor, pressed to do something, went on stage without any help at all, transformed, and the play went on. My friend in the meantime fixed the machine. When it was all over, the lights in the theatre came up and my friend walked out to meet the applause. He explained the transformation scene hadn't gone as hoped. He explained they wanted to do it now. So the lights came down, the curtains opened, the machine was on the stage and Nietzsche went through his transformation the way it was planned.
The punchline? The audience thought the play was supposed to happen in exactly that order.
What I'm saying is that if you screw up, shut up. If the overall performance is high quality enough, it won't matter anyway. The audience will believe what they want to believe.
There's no sense in popping their bubble if you don't have to.