John Wright wrote:

Absolutely. I can think of one bus stop between RAF Halton and
Wendover which is absolutely adjacent to a traffic island. If a bus
stops there, any other traffic has to wait till it moves. If that's
not causing congestion I don't know what is.

I think all of the bus stops in Claremont Rd NW2 are like this. There are no
real opportunities between stops to overtake a moving bus either.