I still think one point is not being stressed enough. There are songs for which we have a long history in broadsheets, music books, or whatever, and for these we can say what the original was, and how it was changed down the years. For songs without this history, all we know is how it was sung at the time it was collected. We do not know if this was the original song. From the songs that do appear in different collections, we know that they are not always (normally? rarely?) identical. Singers have been changing songs throughout history. In that sense Bert Lloyd was very much a part of the tradition he is being accused (by some) of perverting.

There is a store of recorded folk songs, there for those who care to go looking for them, and the songs live on as the singers change. The collected piece is one slice though the history: not holy gospel as sometimes implied.

One divergent thought has occurred: how much does the modern emphasis on copyright drive the rate of change of these songs? Does the need to produce something different mean that change is much more rapid than in earlier times? Perhaps I'd better raise this in a separate thread, but I'll leave the comment here.