In my experience, threads that criticize Montana are NOT closed just cause you say something negative.
In my experience, what does tend to get threads closed is
1.) length, like those 18 pagers on the diamond studded tail gates, for example!
2.) When posts start getting personal in a negative way.
I'd suppose there are a few other reasons for threads to get locked.
Generally speaking I believe admins and moderators do a pretty good job of knowing when to shut us down. I sure am glad I don't have to make those decisions. GULP!