When I hear Dylan singing his songs and constantly departing from his original
recorded melody, it tells me he doesn't have the same connection to melody that
his fans have. He is interested in not boring himself and so if the much loved version has to go, so be it. In other words, a tune is not quite so precious to him as to some others. Thus, he might use Nottamun Town as a basis but he won't have that
reverence for it that a folkie, say, might have.