Flashy,
The "plainly see" part was purely rhetorical. You have to trust me when I describe something.
Also, I have every right to interpret and analyze and make conclusions. If they're right, they're right. If they're wrong, they're wrong. This is what people, animals, conscious living creatures do. You're going to be judged. Deal with it and correct when you can. And you're right, I can't experience complete heterosexuality. But that's supposed to forbid me from talking about it?
I wasn't commenting on, or attacking, your sexuality. You know what you are, what you like, etc., at least mostly and up to this point in time. I was commenting on your definition of sexuality, which seems to not take into account psychological and emotional aspects of sex. Tell a rape victim that all she had was sex, and you'll see that you can't separate the two. If you're interested, there are many scientific experiments online that talk of the entire brain being active during sex, not just specific regions like the amygdala.
As for fluidity of attraction and arousal, I'm a good example of that "myth," although I can't really prove it here. You're going to have to take my word for it. It probably isn't true for you. But you have to admit that you can't really know this one until the last second of your death. Wouldn't it be funny though if after a lifetime of fantasizing and having sex and emotional connections with women, just as you were about to die an image of two guys doing it flashed in your mind? Last words: "Aw, fuck..."
You seem to be extrapolating about other heterosexual, gay and bisexual people, which is the same thing you deride me for doing. You also seem to be generalizing about what other people find attractive, as if all heterosexuals find the same things attractive. I'm saying here that it's okay to talk in terms of generality and conjecture, because it's unavoidable as far as the human condition is concerned. All we can do is learn from it, so there's no need to get defensive about any such discussion (unless you weren't and I'm getting the wrong inflections, which is such a fucking downer about internet chatting).
Also, what you and I find beautiful and erotic might be surprisingly similar. I do think girls are hot as well. Oh, and sorry about my philosophizing. Can't help it.