Your/Dick's description is beyond my comprehension - I don't read music an didn't the vast majority of our folk singers
As I understand it, Sharp went far further into musical analysis
Out folk songs are word based and narratively formed (once again) the tunes provide a form for the poetry and are unimportant in themselves (in England anyway) as they are transient and constantly replaceable.

By the way
WHAT ON EARTH HAS THIS TO DO WITH FOLKSONG !!!
Jim