I strongly suspect that the people making serious contributions here are very close in their definitions of 'traditional singer' as is the OP. The fact that these definitions don't occur as such in dictionaries shouldn't matter to us.

I agree fully with your 7.44 posting, Howard. I'm sorry it depresses you that most people interested in folk music don't need hard and fast definitions. It's their prerogative. Just showing interest doesn't mean you have to analyse and define everything. That's just for us nerds!