I don't like to be indelicate, but let's clarify. I found myself in a typical ladies' cubical. The kind where there are gaps in the sides and people don't see what you are up to because they choose not to peer through the gaps. A young male of 5 feet tall peered through at me as I tried to deal with my menstrual hygiene. I was uncomfortable. I did resent him being there. It did cause me to wonder what in the world he was doing there anyway. I felt some deep social norms had been transgressed and my privacy had been rode rough shod over.
Now, I asked my question on MN rather than saying or doing anything there on the spot. I'm glad I did because until reading this 13 page thread, it never occurred to me that the both the young man's presence and behaviour could be explained by invisible special needs. Looking back, this was probably the case. And the mother has my sympathy and of course I am "over it."
Most folks with normally developing (is this the polite lingo?) children have said that their kids started using the loo around 6/7 and were pretty much independent by 8 unless the loo was particularly worrisome. I've got no problem with this. Seems reasonable to me.
I do think the Mums with DSs with SN will eventually have to find a new strategy because puberty will occur and there will be no way they can acceptably bring these boys into the Ladies' loo. If they want a few more years of life being a teensy bit easier by being able to take the boys into the ladies loo rather than searching out a disabled loo, then fine with me.
And one final thought, while I agree that the public gents bellow Leicester square would be a crazy place to send a boy on his own, why this deep fear of men generally? Surely in most gent's loos the men in there are simply our fathers, husbands, brothers and sons, not all manic rapists. Would a normal man feel comfortable helping a little boy who ran into trouble in the gents, the way I am sure a woman would help my daughter in the ladies loo if I wasn't there? Or would he fear that any approach would endanger him of appearing to be a peadophile?
Phew!