"it happened with (white) blues collectors who went in search of the "authentic" and disregarded much that was also in the repetoire of the players. This included chunks of jazz which didn't fit with the conception of what the unsophisticated should be playing and also cross-overs with "white" music"

So then I guess the "ignorance" that Richard spoke of earlier was really misplaced. It looks like this whole falacy of traditional folk music has been perpetuate by some really ignorant people.