New sociology research reveals that married men do less housework than single men, and that the more a man does to keep the house clean, the more often he will have sex with his wife or girlfriend. Neither of these results is surprising, even when you find out that most of the men in the study believed that chores should be equally shared. The primary investigator says "the way that marriage has historically been constructed prohibits and reduces the ability of men to turn their beliefs about equality into an equal division of labor." In other words, unconscious forces nudge men into traditional roles. The power of cultural norms is often only broken when we notice it, examine it, and consciously reject it.
The increase in sex enjoyed by couples who shared housework is easy to understand too. There is a direct correlation between intimacy and equality. If men and women (be they married or simply co-habitating) share equally in the running of the home, they both become partners rather than one leading/nagging the other and criticizing his quality and quantity of work (or silently seething). When partners are equal, they walk in each other's shoes every day, they share the burdens of all tasks, and this makes them attractive and attracted to each other. Life is good!