My mom and dad taught me to be nice to women and protect them. I am never going to hit a woman as hard as I am a man, if something goes wrong, I trust the increased mass of a man's body to absorb the blow better than the typically leaner musculature of a woman.
Bear in mind that I have trained with some women (one in particular) who are capable of physically intimidating me; I'm still bigger than them, but they are probably physically superior to me, in those cases, they get the full deal. I KNOW they can handle it.
I'll also take quite a bit off the top for a man who appears to be physically frail or less capable of taking a poorly distanced or timed strike. It's not purely a gender thang, but my caveman's categorizing mind finds it easier to break it out by sex rather than endomorph, ectomorph or mesomorph.
Some guys (me specifically) are always going to see women as different, and not too suprisingly, they are. Not less, simply different. All differences are okay, and they should all be recognized and accounted for. If a woman trains with me and feels that she is being given too much slack, all she needs to do is turn up the juice a bit, and I'm not too thick to notice it, and I'll respond appropriately.