In reply to Stringy:
Unless they get over the offensive/abusive hurdle (as a thread rather than just one or two posts being deleted) then I think the only threads that get taken down as a matter of course are ones that get into the Israel/Palestinian/anti-Semitic area unless they stay very specific to some particular aspect (which of course never happens and apart from being repetitively tedious these threads usually end up over the offensive/abusive hurdle as well ).
You could always check with Alan what their "taking threads down" policy is.