Regarding rock stars remembering where they are, there is a Spinal Tap guest shot in The Simpsons where one of the Tap looks at the back of his guitar before shouting “Hello Springfield!” Despite this kind of tactic, bands have got it wrong several times.

And as for lyrics, great bluesman Jimmy Reed had his wife Mary Lee come on stage with him. She would stand next to him and remind him of the lyrics very frequently through the show. This was partly because he was almost always too drunk to remember them himself, and partly because, it has been acknowledged since though at the time Jimmy took ful credit, she wrote or co-wrote many of them.