This is one of those rare threads where I start off with one opinion, nad after posts are made, I change my mind.
If it has been done before, my guess is that it worked.
I cant see it getting policed properly, and probably it shouldnt as the cost would be huge, but like there are quiet carriages, there could be ladies only ones.
I dont particularly like the idea, but I can see that at certain times, perhaps later at night , and footbal matches etc, they would have their place.
I also dont like the idea of segregation at all, but can see that occasionally choosing it may be useful.