Hey, when I was at university in Australia our residential dorms had co-ed toilets and bathrooms. You walked in and there were a row of four doors. Three were toilet stalls and the last one was a bath. They were officially unisex and this in an institution of 200 students run by Catholic nuns. In the years I attended there was never an incident. When you rode the porcelain bus you never knew if that pair of shoes or the rustling next door were a man or a woman. It worked....god knows how, but it worked.
No incidents. Except for the night my clothes and towel were stolen from the change area. My entire room was also emptied of all belongings with only a bust of Beethoven left sitting on the floor, in the dark, with a desk lamp shining down on his marble visage. I was then hijacked in the corridor and chased throughout the building with nothing more than a wet, transluscent shower curtain to save me from an awful accident...
Hang on, did I say a moment ago that these stupid unisex bathrooms worked well????