Why predicted gridlock almost never happens
So blocking up a road results in fewer trip in the affected area?  This is news?  Block up two roads and you will see even more reduction.  Heck, block all the roads.  Traffic solved.<p>Local congestion is only half the story.  How many people simply altered routes, perhaps traveling longer?  How many instead went elsewhere rather than not go anywhere?  I want to see not a city-wide but an area-wide measurement of total miles travelled.  That number matters more (economically, environmentally) than local congestion.  If cutting traffic in the city core results only in greater traffic elsewhere, that is no net good.  In fact it only contributes to urban sprawl as people travel further to reach various destinations.