Intersections are the bottlenecks of the urban road system because an intersection's capacity is only a fraction of the vehicle flows that the roads connecting to the intersection can carry. The saturation flow rate, and hence the capacity, can be increased if vehicles can cross intersections in platoons rather than one by one as they do today. Platoon formation is enabled by connected vehicle technology. Increasing the saturation flow rate has dramatic mobility benefits: the throughput of the road system can be increased, or vehicle queues and delay at intersections can be reduced. These predictions draw on an analysis of a queuing model of a signalized network with fixed time control and they are validated in a simulation of a small urban network with 16 intersections and 73 links.