God, what a bunch of po-faced, snobbish, self-regarding twits this thread has thrown up. If you know it and you get asked for it, why not just play/sing it. You don't have to do it all night. Some of you lot remind me of a great joke that I heard Marilyn Middleton-Pollock come out with. "You're a folk singer, are you? OK then - depress me!" Once or twice an evening it doesn't hurt to ditch "the message" and spread a little happiness instead.