Totally fantastic. Completely outdoes some other amusements, like the supposed Hendrix "kiss this guy" thing.
And in re Cocker: you can't get there with false drugs. Not that people weren't constantly plying him with them.
Kathryn King told me a JC anecdote. I think it was at Kendun, here in LA, and this very nervous and chronically edgy producer was cutting a disk---the final opportunity in those vinyl-only days to make final tweaks on the EQ etc.
The production involved, among other material, some spoken-word passages of a political nature.
Cocker was wandering about the studio complex, and came into the room unannounced. They were about 2/3 through the cutting, and tension was already very very high. Not a word was spoken, and as he entered probably breaths were drawn and held.
JC listened for a little while, decided he didn't like what he was hearing, and walked over to the rolling tape machines.
He reached out and hit Stop.
I don't recall if the producer actually required immediate hospitalization or not.