I think it takes more than four drinks, but Pedro once woke up on the floor the morning after a party being spooned by an otherwise extremely straight (and very attractive) man. He was very weirded out, but manged to extricate himself without waking the other dude, and we agreed to never speak of it again.
Until now.
But yeah, I was really just being combative, but I do think that there are guys who are latently bisexual who could be convinced to get up to dude-on-dude shenanigans as long as they have the fog of booze to blame it on later. Not many, but they do exist. Yeah, they're bi when sober, too, but they'd never act on those urges until you get some liquid courage in them.
Ladies, on the other hand, are more likely to make out with other ladies because dudes dig it, whether or not they are in fact harboring actual bisexual feelings. I know several girls who have gotten it on with ladies to please their men, which does not make them lesbians so much as actresses.