theres a great book called Ireland a tin whistle and a bicycle. About a fellow traveling around Ireland and going to all the sessions. At one point he's in a pub in the North having drinks with some bikers. They see that he has a guitar so they make him get up and play. He goes through a number of tunes and they request John Denver. He doesnt know any, "Play some John Denver or well kill ya". somehow the words to country roads make their way to the forefront of his mind.