I have certainly experienced what you're talkingabout: advised musically minded friends to take a look at Mudcat, they might find something interesting, and they come back and say "Oh yes? Where?" All we can do is try and start interesting music threads, I suppose, and try to avoid getting too involved with the otherstuff. Trouble is, there is no obvious solution to the anonymous or pseudonymous skilful shit-stirrer, who is not arguing but role-playing. Presumably the people who run allthis attempt some sort of control, but I don't know enough about computers to know how much can be done in the way of access-denying to identified computers. i think we can mostly cope with good old-fashioned bad temper and bad manners, but some of the other stuff can be really creepy.
Anyway, there are plenty of music threads running at the moment: dig in!