Kinda went off on this on Facebook last night. Glen Campbell developed Alzhiemers a few years ago, and somehow while having all the difficulty you'd expect, could still play, so he decided to tour once more. He needed a teleprompter for the words, but the guitar stayed with him for quite a while. Audiences were really understanding. (One woman said "if he want to play Wichita Lineman twice it's ok with me!") This is Dueling Banjos by a guy who can't find the bathroom or even remember he has a show to play:
"You just need to go at that shit wide open, hang on, and own it." —Camp