Some singers resent tunes because they cant play an instrument, they need to understand that their voice is an instrument and the sooner the better. I have been in many a session and seen the steam come out of there ears and quite frankly they ruin the session. BUT there are also certain musicians who cant sing that dont like, as they see it, the singers getting the upper hand and becoming dominant in sessions. I'm fed up with hearing the moans and groans, and the regular comment in "folk circle" environments "its my turn and she/he has gone before me. They need to realise its like farting, everone gets a turn. I wish they would stay at home and play with themselves.