A lot of what Behrendt said is utter bs. There are plenty of reasons why guys don't ask a girl out even when they're extremely attracted to them; for this guy to just dismiss them, and characterize all males as 100% sex-driven machines, is pretty disgusting.
As for whether guys have to initiate in relationships...obviously there's the social expectation that they will, and in the majority of cases they do, but if you're a woman, please don't believe this to be an absolute rule. If you want a relationship with a guy, or you want to move an existing relationship forward, just go ahead and ask, the majority of guys will appreciate it. I would agree though that this shouldn't be done more than occasionally; not only do most guys like the thrill of the chase, they also tend to value the women they have put a lot of time and effort into more.