Thanks for pointing that article out. I will give it a read in the next few days. I did like this bit from an interview with Frank Buckley Walker by Mike Seeger in 1962:

"At one point during the interview, Mike Seeger asked, "In the early days, they seemed to record a lot of English kind of ballads." To which Walker replied:

That is right. That's where so many of these things came (from). And yet, it's a strange thing that you could take an English ballad of some sort and it got its way to this country and it settled at the foot of a mountain in North Carolina, and it had words put to it by the people in that area down through the years. And when you go to the other side of the mountain and you find the same tune, the same melody but with a different set of words, to fit their likes or their particular location. Originally much of that came from England and Wales"

I like the idea of songs settling at the foot of a mountain waiting for someone to carry them over.