The metro will help because it can get passengers from the T3 and the T1 upper shore out of town hall and not because it created a bottleneck around the circle. There used to be 24 train an hour back in the single decker days and so the signalling system is clearly not the reason for the current 20tph limit. It is the trains, the platforms and the passengers that cause this limit. Olympic park can see more then 30 trains an hour during the busy parts of the easter show or other big events with the current signalling.....and more to the point, dual very wide platforms per track which prevent departing and boarding passengers from mixing and thus causing a back log into the train of departing passengers.
- No automated doors delay
- No "stand clear, doors closing" delay
- People started departing the train before its stopped
- People still boarding as it departed, guards would let trains leave knowing there were a few guys running to the train and would board while the train is moving.
- Overall less people to get off per car
Moral of the story, the dwell time is a probably 2/3 to half of what it is today.