Cap'n Birdseye said:
"Respect for your material is important,and I wouldnt encourage an audience to take the piss out of a song......a good performer knows how to deal with it,how to turn it to his advantage and how to win his audience,lecturing people does not work."

We are talking here about source singers, I believe, and not professional performers who are there by choice. Some of the old source singers who were 'discovered' by collectors, and who had been encouraged to perform their material for interested audiences would have been completely unprepared for such a reaction as described. Such disrespectful behaviour would never have happened when they performed within their own milieu and, in my view, should never have been allowed to happen when they so generously shared their art with folk audiences.

So that makes me a member of the folk police too.