I don't actually see how much influence the existence of other versions has. Sure, they're around, but how many people are going to go back to find them? How many people will go hunting for a recording of Arthur Crudup doing "That's alright mama" when they have the Elvis version? If they're real completists then maybe, but most people won't. So the chances of everyone going back to the original are pretty slim, and hence the folk process will go along quite nicely with everyone changing a bit here and there as they prefer.

Incidentally, there's talk here like we're the first generation to ask this question. We're not - the first generation was the generation that invented the printing press and enabled cheap reproduction of sheet music, and that's been a few years back now. There's a whole bunch of people now looking back through the Bodleian and other archives to find the sources for some of these songs, but anyone could have done that at any time in the past, and they didn't. Even at the time, anyone could have asked around for the original broadsheets, but chances are that they didn't.

Graham.