Why is the woman not responsible for her own decisions? Why is the man responsible for his own decisions plus ascertaining whether the woman is capable of making her own decisions or incapacitated regardless of whether he's incapacitated??
Your analogies are wrong. Try it this way: you and a buddy leave a bar and screw cows. You do it because you're drunk, and, well, you're also into bestiality. He does it because he's "terminally drunk". Why am I to assume that you knew he was not into bestiality and deliberately conspired to get him to screw a cow with you? How do I know that you did not just assume that he had similar desires as you, and wanted to screw a cow like you did? Why is he an unresponsible actor, and you bear responsibility for your actions as well as his?
I see a lot of defense revolving around the "both too drunk to know what they're doing", basically. While that raises a lot of philosophical questions, that's not the only case by far. You don't even need to research much to end up with advice to deliberately get someone drunk to screw her, and all the way to jokes, cartoons and t-shirts on the topic of "how to know when she's drunk enough." That's a decision taken while the one doing it is sober, not some spark of lust after both had the 6'th pint.
Basically I'll even grant a perp the
drunk defense, if it was indeed a bad decision taken while too intoxicated to think straight, but not if the premeditation part happened when sober and only during the execution he might or might not have been actually drunk.
Second, it's hard for me to take the, basically, "the bitch wanted it" defense seriously, when intoxication is often considered a mitigating factor even in criminal acts. Between someone who took a bad decision on an impulse while drunk, and someone who premeditated it while sober, I'm sorry, but I see no problem with giving the former more of an excuse than the latter.
Doubly so when in some cases we're talking someone who isn't just intoxicated enough to take a bad decision, but too intoxicated to defend themselves or even unconscious. That was actually the scenario explicitly asked in that survey quoted above. They didn't ask if they had sex with someone who was drunk enough to like them, but explicitly someone too intoxicated to defend themselves. I don't see how _that_ would count as her responsibility.
Also, the hypothetical scenario I was answering to, explicitly was talking about someone she doesn't like and about being "soo drunk". It's a bit harder to justify than someone needing a pint to shed some inhibitions and screw someone she does like.
Third, in your analogy, I can't stop that guy from screwing a cow too. I mean, I'm not his legal guardian or anything. But I can refrain from screwing a woman that I got drunk. Or for that matter from planning to get someone drunk or find a drunk chick to screw in the first place. It's not the same level of responsibility at all.
Fourth, a couple of of the guys in that survey essentially confessed to committing over 100 rapes. While I could imagine someone doing a bad deed once only because they too were too drunk to think straight, coming back the next day to do it again, and then again, and again, is where it starts looking more like a planned strategy than excusable lapse of judgment under influence.
To get back to the bestiality analogy: If a guy gets drunk once and screws a cow, well, ok, I'll laugh at him anyway, but I can believe that it was an accident and not representative of his normal behaviour. But if he goes back the next day, gets drunk again and screws a cow again, I might think maybe there's something to it after all. And if it happens to him a hundred times, I might think he's actually planning it.