Tell ya what Sminky, I've heard far better music being played by the so-called "peripherals" than I've heard in many a folk club or at many a concert.

There are remarkable abilities with in the ranks of buskers, amatuer floor singers ans session players for sure and personally, in terms of musical ability, I think the best from these areas are more capable than some pros.

I'm not sure that provides a full or fair picture though as sheer musical ability is not (at least as far as I can tell) the only factor in giving a good performance. What I'd expect more than anything if say I was (not that I do) booking an act for a folk club from a pro is the ability to relate to the audience, perhaps assess the mood of the room, etc.

I've never been there (and never will) but I think there's a whole range of "stage craft" needed say to hold an hour together that many amateurs who might be able to turn out a blinding song, tune or two probably don't have.