Felix what you apparently fail to see (no matter how often it is being pointed out to you) is that even in cases where it is not an issue about ‚ he said, she said‘ an excuse will be found to not convict the rapist.
Like that case of that girl in the US - Rehtaeh Was her first name (Heather backwards). She was so drunk, she couldn’t mumble a word, the assault was on video, the guy bragged about it. But the case couldn’t be prosecuted, because she didn’t say no and was obviously too drunk to remember (as evidenced on the vid), and at the same time, her face was not clearly identifiable on the vid (only her hair and limp body and the perpetrator were).
She changed school (perp was a class mate), couldn’t take it and ultimately killed herself and only afterwards there was this ‚heureka‘- moment of ,actually, maybe the police could have prosecuted, considering the video evidence…
As long as even the most obvious cases get dismissed for self-contradictory reasons, the question about written consent is academic, because OBVIOUSLY even when you have video evidence of a guy violently penetrating an unconscious woman, it will get dismissed. So, what would anyone need a written consent form for?