Give me a fucking break. It says right in your profile that you are 20% straight. But you're going to tell me that's not because you fucked a woman, right? Sure.
If that one woman were measured against my male partners, I'm about a third of one percent straight. But this 99.66% gay-experienced guy cannot legitimately be called gay according to your theory because of that one woman. Throw me in the bi category along with every straight guy who ever got a single male bj. That'll make the male population half-bisexual with straights in #2 position and gays a tiny minority. But you'd be stretching the definition of bisexual so far as to make it unrecognizable.
(btw 80/20 is a measure of orientation, an attraction to men four times as strong as to women, and whether that is bi or gay is a matter of semantics)