Yes there was also some research done on young men who were asked how they turned down sex if they didn't want it. Many of htem were horrified when asked if they just said a straight out bald "no". "Of course not - I'd say "I've got an important presentation tomorrow/ early start/ not feeling too well -would always let someone down gently, I woudln't want to embarrass her" was the gist of their responses.
This from the sex who haven't been conditioned from birth to consider other people's needs more important than their own. Yet even they find it excruciatingly embarrassing to just say no, they make polite, socially acceptable excuses to save everyone's face, because that's what we all do if we're nice, considerate, normal-ish people.
And yet women are supposed to be more assertive and clear than these young men, who are not actually in any danger or fear, even though they have been specifically given the message from birth, that assertiveness = nasty person. When they're scared and feeling trapped. They are supposed to make themselves clearer than young men who are in no danger of being raped.
Those same men, when watching a video of a rape scene, all said that it wasn't rape, because she hadn't straight out said a clear, unequivocal no. She'd hedged a bit, been polite, made excuses, was ambiguous - just like they all said they did when they didn't want sex. But the consequence for them, wasn't rape.