Well, even though people hate 'trolls', there's no mistaking the debate and activity they stir up.
I've learned a lot about BM from reading the troll threads.
Anyway, what you resist persists. Most persistent trolls seem to somehow thrive on the attention they get.
I've seen entire Usenet newsgroups become paralyzed by one persistent and antagonistic troll.
If I was an admin here, I'd set up a troll poll. When any user gets more than 10% of the users voting them a troll, I'd move their new threads automatically to a rants and raves thread when posted.
They still get freedom of speech, the rest get some relief from incessant yammering on their obsessive themes.
Of course, a moderator could do the same thing. Troll can always get new user names but at least these threads would eventually have a home of their own out of the main conversational channels.
Short Attention Span Theatre