I've had many feminism discussions - they tend to wear me out. 
I had one yesterday on another blog - I still feel completely drained. (of course, lousy sleep due to my air conditioning not being able to deal with the heat wave we're having right now doesn't help)
Even if you're largely on the side of women, any degree of disagreement tends to get you labeled as privileged, sexist, or misogynist. I think it's true that a man can't fully understand the perspective of women and how they feel about certain issues, but such charges tend to make any kind of rational discourse shut down. You have to walk a tightrope and if you lose your balance at all there's no recovery. You want to have a place in the conversation, but if you aren't towing the party line your opinions are regarded as completely irrelevant so you're inclined to just stop talking about it altogether or you only discuss it with other men and don't get a female perspective.
Frankly I'd rather deal with the actual misogynists - at least I don't care what they think of me.
