Watching this after reading the excellent duology by Peter Guralnick helps you see past the supposed glitz to a picture of a man spiralling out of control to his death. Yeah, he had 5 years left, but he was getting fat, hooked on pills, and surrounded by insanity and yes men even here. It's like he was just about to step off the plank to become fat, joke Elvis, his last hurrah.
Worth seeing as a historical curiosity though.