And of course you missed Richard's point which is also something that has irritated me. That is the implicit assumption that folk music equals a singer accompanying him or herself on a guitar.

Without wishing to get into the "what is folk music" debate, that does seem to me to be an unduly restrictive definition of folk music. There have been hints earlier in the thread that others think likewise. Certainly here in the UK, folk music seems to mean more than just singer - guitarists.

I have always been under the impression that bluegrass can be considered a genre of folk music - even if it does have a strong commercial element. But then maybe that is a naive UK perspective.