I have very little tolerance for idiocy or circular logic. I also refuse to get baited, although occasionally I'll join in a snark fest.
Outside of feminist groups, there is very little productive discussion about gender issues, unless it's to somehow degrade feminism, or subvert feminist issues. For instance the majority of DU'ers, not all but the majority are pro choice, but many won't acknowledge that as a feminist issue, certain members seem to want it to be part of what I can only call a 'libertarian' agenda. Sexist language can't be discussed without it being called censorship-- I'm not the language police either, but generally, although any other kind of bigoted language is not tolerated, sexist language is so embedded, discussion is impossible.
Lately I've been talking to co- workers, who say their husbands 'don't understand' the disparity in women's issues, such as health care, so I'm not sure how far off DU is from the regular population. Interestingly, my co- workers are often much more conservative than I am, but even they can see it.
On the other hand if you have a thick skin, a high tolerance for stupid people, and are difficult to bait, it can make a huge difference in a thread. Beware-- decent logic, and well thought out arguments will be ignored or you'll get labeled 'meta'. Bains posts some of the most logical arguments out there, and is constantly be labeled this or that. RedQueen will start threads about important topics, which instantly get derailed.
In short, arguing with some of these folks is like herding cats, they go off In every direction.