Streetcars will stop less frequently because their signals will be coordinated with those used by east-west vehicular traffic. That means both streetcars and vehicles will travel together giving streetcars the maximum amount of time to clear the intersection.
The system will include up to a 15 second extension of the east-west green if a streetcar is within a close distance of the intersection. If a streetcar is waiting, and there are no other vehicles in the area, the system can also shorten the length of a red light at a north-south crossing. This will help reduce the number of times a streetcar is stopped at a red light.
The corridor will be optimized to ensure that traffic signals are coordinated reducing the number of stops and starts which lead to slower overall travel times.
I am somewhat disappointed with this transit priority for Queen's Quay. It sounds exactly like the system we use everywhere else in the city, which has serious limitations. Combining the greens for transit and east-west traffic will no doubt improve operations, but the priority system itself is not that spectacular.
The 15 second extension is surprising, because normally we use 30 seconds at minor intersections and 16 seconds at major ones. Maybe it's related to the small block length, which limits the advance detection distance.
There is little to no opportunity to shorten the green for cross streets, because they are almost all minor streets. Minor streets tend to already use the absolute minimum green time required for safe pedestrian crossing. Once the walk light turns on, the signal is locked in until the end of the flashing don't walk. Whether or not there are vehicles in the area is completely irrelevant. Besides, giving the main street a green light when no one else is around is not transit priority, it is ordinary traffic signal operation.
And when they talk about co-ordination, they fail to actually specify that the lights would be co-ordinated for transit. After all, if there were an effective transit priority system, why would we bother? I think what they are saying is "we'll co-ordinate for cars, but that might help transit too".
The city always co-ordinates signals for cars. Even when there are more people cycling than driving (Harbord), or taking surface transit (Yonge north of Finch, Dufferin, etc.). I've been told that they would need approval from the very top in order to implement my suggestion of co-ordination for bicycles on Harbord.
Background info:
The old Queens Quay used a unique signal system called Aries because the city's main signal system at the time, MTSS, was not flexible enough to allow a setup with dedicated transit phases callable at any point in the cycle. The main system the city now uses can do that anyway, so there would be no point in maintaining the standalone and now-obsolete Aries system.
