In answer to your actual question: I don't see why it wouldn't work on humans, I swear I got a reading before the cat scarpered.
Sweet, good to know. Come to think of it, Ray's bartender was probably a cat rather than a human, so this actually answers the question I should have asked. (I forgot they were cats. It happens to the best of us.)
As for the some-guys-liking-dumb-girls phenomenon, once in my life this conversation happened:
Math Girl: You know what's lame? Sometimes a guy will hit on me, and when he finds out I'm a math girl his first reaction is to be all, "Math, eh? Well, I know a thing or two about math myself. Probably more than you do, in fact, even though you're getting a degree in it and I'm not. Maybe I could help you with your homework sometime."
Math Boy: You think that's lame? When girls hit on me and they find out I'm a math boy, their first reaction is to go, "Math? Gee! Math is hard! I've got no head for figures! Maybe you could help me with my homework sometime."
So it seems like for a lot of people, male and female, heterosexual courtship means putting on a performance called "girls are dumb, boys are much smarter" I don't know if they drop the act once the relationship starts or if they keep it up indefinitely.
Also: When I see models in magazines I am less annoyed by the fact that their bodies are photoshopped to be unreasonably thin, and more annoyed by the fact that their faces are photoshopped to look uniformly dumb. They've all got that identical vacant "come hither" look, a look that says "I'm a non-player character who's programmed to want you." So apparently someone out there looooves dumb as much as ray does, although I couldn't say whether it's the editors or the readers.