No, I am not going to ask why they have separate hot and cold water faucets. I know they are people who will endure anything so long as it is traditional.
I just got back from one of my trips to London and noticed the same things I notice on every visit (they speak funny, the trains in the underground are tiny, electrical plugs are huge, etc). Among the things I always notice is that you see little pipes sticking out of the exterior walls of houses and buildings and sometimes water is coming out of them. I asked around and it seems they are overflow pipes for the toilet tanks. If the water valve does not close completely the water flows out this pipe. I mentioned that in the rest of the civilised world where toilets are also in common use, the overflow conduct goes directly down to the toilet bowl. But in England it has to go outside which means a long pipe if the toilet is not near an exterior wall. I have seen exterior walls stained by water that must have flowed for months.
What is the reason for requiring this overflow pipe to go outside? No one in England has been able to explain it to me.