I am always bitterly amused when I hear people say that homosexuality is a choice. Even many otherwise thoughtful people maintain that the homosexual is a heterosexual who perversely ignores, or at least somehow represses, his natural cravings. I say "otherwise thoughtful" because I know of no position which collapses more quickly, under even a moment's examination, than this one.
Never mind the obvious question of why anyone would choose homosexuality, with all the inconveniences and confusions and difficulties it poses.
Let us suppose, for argument's sake, that there are people who declare: "Actually, I would prefer to be (probably) childless, to face a hundred kinds of social difficulties, to disappoint and maybe horrify my parents, to risk alienating myself from some of my friends and many of my peers, to be an object of disgust and scorn to many millions of people. Sure. Sounds fun."
Timely if you've read any representative portion of the comment section on the Sports Illustrated article in which Jason Collins announced he was gay. I can't find the comment section for that piece anymore, perhaps Sports Illustrated took them down, but many argued the article proved Collins had chosen to be gay.
Comments sections, for the most part, are sobering reminders of what people will write when they can hide behind the cloak of anonymity, but Rauch, who is gay himself, provides a very powerful argument against the idea that being gay is a conscious choice. From an incentive standpoint, it's not a choice anyone would opt for in a rational actor model.