The singers club had a reputation, the one i knew was that it was prescriptive.although to be fair as performers the residents all had very good reputations as performers
ok, i have listened to the performer you mentioned, Dave, i am not sure the songs i listened to are folk songs, however he is a good performer of his comedy songs and other songs, personally i would rather listen to Martin Carthy who does sing folk songs, but that is personal taste, and no detriment to the perfomer you mentioned.
What does annoy me are the less competent singer songwriters who are not american and sing in false american accents.