I know this is anecdotal but you just notice it more when women are bad because there's so few of them around. You can usually tell when they're subpar because they think they're too attractive to learn the mechanics of a fight. You tell them little tricks and they refuse to take that advice. For example, when I am on my hunter in a hard raid, I will tether that middle room 3 times on totems. I tether upon entering, I kill that wizard, kill the stuff I tethered (BLACK HOLE), my super is then usually charged again, so I tether again, then when someone says "Switch" I tether and don't kill (I have to get back to my totem) but I let the others kill my tethered mobs. When I see a "gamer girl" play I see 1 tether in the timespan that I do 3.