"How does NERFA define "folk"? "

The good thing is, they do not try to. I echo Bill's comment (and thank him for the kind words).   Music does not need to fit into anyones definition to be good or bad.   

When I was a kid, I hated vegetables. Not that I tried them - I just hated them because they were neither meat, pasta or desert. As I grew older I realized that I was missing out on a tasty and healthy treat because I let a word and a perception cloud my judgement. I won't do that with music.