Ya, that's really messed up. :-\
I remember hearing something about filming for the movie Jesus Christ Superstar, in which one of the characters (possibly the character "Jesus," I don't know, I never saw the actual movie, lol) had to be hung. They had some kind of setup where the noose went around his neck, but was supported at the back by some kind of hook thing. Unfortuneatly the hook thing didn't work at all, and after 30 seconds of "superb acting" they started to realize something was wrong. The actor ended up being ok, and they may even have used that actual take, but still, that would be terrible to have everyone just think you were "acting out" a life and death situation when in actual fact it was a life or death situation. Crazy stuff...