I can see a situation where an intelligent system would "spread" the traffic over all available routes. Unless the area was completely gridlocked, each driver would perceive less delays, although whether their journey was actually any quicker is a different matter. Taking a rat-run through a housing estate, allowing for speed bumps & 20MPH limits, seems faster if you aren't stuck behind other vehicles, until you try to rejoin a main road. Weight of traffic may well stop you getting onto the main road, for a longer period of time, than if you had stayed with the main road in the first place!
TomTom Go 940 LIVE (9.465, Europe v905.4754 on SD & 8.371, WCE v875.3613 on board)