The key thing - long lost in London - is for the bus shelters to be in the right place relative to the stops. It's no surprise that the idea of queueing for buses has gone out of the window in London (leading to vulnerable people being left behind by several buses running, at busy times) given that the shelters are no longer automatically "downwind" of the stop, so people starting a queue at the stop, and looking in the direction of the bus's arrival, no longer have the queue tailing back under the shelter. Apart from a handful of instances where road layout etc required it to be different [which is what you're calling "tailstops" here, is it?], it was once almost universal to have stops and shelters placed in a way which made queueing sensible and obvious.
I remember that when some stops near Kings Cross were replaced a few years ago, one of them went back in the "wrong" place relative to the shelter; "queueing discipline" collapsed overnight.