Again, it's true when you only talk about attraction, and it certainly works with the majority of women. Not that the rest isn't biologically attracted to what you just describe, but if we give my example, when I smell the vibe of playfulness, even If I'm really attracted to the guy, I choose to backup (by playfulness I don't precisely mean a guy who is dating multiple women in the beginning, because for me it totally makes sense, but, the vibe).
I think that either men nor women should be exclusive unless there is a sufficient engagement from the other part, but why does it have to be the woman that is slightly more engaged ? Why shouldn't men or women follow their intuition and the product of their thinking instead of rigid rules that are impossible to break ? It makes me uncomfortable when I see rules in dating for both sexes, what we need to have in my opinion, is general principles that we follow, rules can never match every situation and every person (man or woman).