Nigel Goodwin said:Flashing headlights at traffic lights has long been a myth, as far as I'm aware there's no traffic light over ride for emergency vehicles in the UK? - they simply go through at red - relying on all the traffic stopping (which it does).
In the big cities, many intersections get jammed up with cars, and its best to keep some of it moving, so they can move out of the way. It's one reason I enjoy living in a small town.