...the reason some gay guys are effeminate is because their instinct makes them act like women to attract men (because thats what most men are attracted to).
...Also if you take a look masculine men are usually attracted to the feminine type because of this same reason.
I already know many of you will bitch about this, but who agrees with me? If you dont, feel free to share your own theory (i know this topic is entertaining for everyone).
A problem with your theory is that genetics is worthless if the individual does not procreate. A gay man who doesn't mate with a woman is a genetic dead end, at least until very recent times with the intervention of science.
Having "fem dna" (and I'm not sure what that is as venue 35 calls it) in order to attract other gay men is not something Nature would do. Nature does things repeatedly that will enhance successful procreation, and does other things randomly, that may or may not give an evolutionary advantage. Fem gay guys are fairly common, not random, and do not procreate, and meet none of Nature's obvious procreation goals.
Unless you subscribe to another theory, that humans, being social creatures, also benefit as a species from non-breeding individuals who assist the breeding population in other ways. In both easing parenting duties of the breeders, especially the men to hunt in early times and assisting the women in child rearing, and in enhancing culture and non-subsistence elements of life.
Some anthropologists are coming to the conclusion that human culture is as important to our thriving as an advanced species as are food & shelter. Therefore, non-breeding gays who make cultural contributions play an important role. But this is a more subtle model than classic Darwinian evolution, and the mechanism not entirely clear. And still doesn't explain fem versus "manly" in gays.
As for myself, I guess I'm an exception to your own model. I like masculine men, not effeminate. Not that I don't have fem friends, but in my love life I like a man who mirrors myself. I must do that, or I'll run him right over him, trample him, without realizing I'm doing it. Having a strong mate is in my best interests, and his.
Same with women. I like independent and strong women. Not dependent kittens and airheads. I prefer people of any sex or orientation who can stand toe-to-toe with me, and be my equal in every sense.
Now I'm obviously assuming that fems are easily dominated. Not all, of course, but most I've seen are. What passes for strength is more often passive aggressiveness, which I happily avoid. So no, bottom line I prefer a non-fem gay man in my life. And I've seen plenty of fem-fem couples, who seem very compatible & happy. So maybe that's the best formula for most of us - guys most like ourselves.
But I see no broad evidence to support your contention that fem guys are made that way to attract other "manly" men, as you put it.