Geni;
If you are talking about swapping songs with friends, you may perform them naked while standing in a bucket of custard as far as I'm concerned. Once you let the public - paying or otherwise - through the door then you take responsibility for those songs and how they are performed and received (I'm talking about folk songs, I've no opinion or experience on the presentation of any other forms). As has been pointed out, folk song has a poor enough (sometimes deserved) image without adding to it by it being performed by people who can't sing and can't remember words.
I heard it said not so long ago that the last thing you would do should you wish to introduce somebody to folk song is to take them to a folk club.
"Really? Who do you think says that standards don't apply? "
Unless you consider 'wanting to sing' a standard - you do. It is not; it is an abandoning of standards. Why on earth should anybody who doesn't want to sing ask to? Therefore you are giving your club over to anybody who walks through your door, whether they can sing or not - there really is nowhere else to hide.
Off to the UK for a few days tomorrow; I wonder if I'll find anything worth listening to - no luck so far; here's hoping.
Jim Carroll