There's a problem with that theory. Yes, it's completely correct on the drawing board. In the real world, though, almost all 9s and 10s are either taken, or getting plenty of attention from attractive guys. They're not going to notice that someone isn't paying attention to them when these two dudes are being charming and chatting her up, her appetite for attention will just be pleasantly sated. Which is why I try to take a more or less head on approach. If I decide I'm interested in a 9-10 (or an 11... yes they exist gentlemen, I swear to you), they know I'm interested within one minute of me talking to them. And why is this effective? Because confidence is the most attractive quality a person can have, and, you said it, they know they're attractive. They know they're wanted. It only helps that they know this, because they know that it'll take a truly confident guy to go head-on after them. As a bonus, even if you're not good looking, it works because it implies you probably have something going for you beyond appearance for you to still have confidence. Like, say, money. Or power / social status.
That's all for today's lecture!