What's more, whether due to nurture or nature, there is usually a difference in tempo between men and women, with women generally requiring more "convincing." And someone who requires convincing is not yet in a position to offer "affirmative" much less "enthusiastic" consent.
The assumption is that somehow one partner (and let's be honest, it is overwhelmingly the one with a Y chromosome) didn't ask or realize that the other wasn't into it.
But the fact is: Most assaulters know exactly what they are doing.
The vast majority of campus rapes are committed by a small minority of repeat offenders who give not a damn about what the woman wants.
And if they can threaten violence, they can also lie about obtaining consent. Feminists argue that the new standard means that campus authorities will now have to grill the accused about whether and how he obtained consent — rather than the victim to prove that she refused — mitigating the trauma of investigations and encouraging more women to come forward. But by changing the assumption from "presumed innocent" to "presumed guilty," this new standard will inevitably snag some guys who earnestly meant no harm.
Over time, of course, an industry of lawyers will emerge to coach the accused on how to game the law and get away.