I'd say that's a very, very simplified theory of attraction that leaves out numerous factors.
While it is likely true that there are visual indicators of health (skin quality, hair quality, physique, etc), there are definitely numerous other factors as well. One that is easy to overlook is scent. It's quite possible the females in particular are affected by the scent of a potential partner, since this can correlate with hormone levels and the compatibility of their immune systems. In choosing long term mates, psychological compatibility is also a major concern, and is a possible contributor to people's willingness and desires to have homosexual relationships. Additionally, there is the willingness to mate that must be considered. A person that shows no interest at all in you will be perceived as less attractive, and one that shows great interest will be perceived as more attractive, this is because any opportunity to mate is evolutionarily superior to no opportunity. It's worth noting that every single factor of attraction (I've probably overlooked some) has a debate of it's own, but in general it seems to be something we understand, even if we can't quantify it.
Seems like bs. Emma Watson can have my offspring though :)
or mine :)
I doubt such theories are necessarily bad science by any means (in theory, I can't say for sure), but and though I would call the human condition unique, I'm pretty sure even most animals (certainly every mammal I know of) have shown different tastes.
I think the general scientific idea is that we acquire taste through centuries of DNA mix-matching. Probably something we'll find evidence of with enough knowledge into quantum physics/mechanics, if you ask me.