Lucas123 writes: The so called traffic study that closed New Jersey access lanes on the heavily traveled George Washington Bridge last September has left engineers scratching their heads because in modern America, simulation software is used instead of closing down lanes. One of the best sources for simulation data are video camera systems that use software to count vehicles on roadways. Traffic studies use microscopic traffic simulations to create virtual environments that can model driver behavior to road changes with exacting detail. Instead, the Port Authority, under Gov. Chris Christie, shut down two of the three access lanes for four days last September from Fort Lee to the George Washington Bridge without warning the public, citing a "traffic study." "I would be pretty confident that if we knew exactly which lanes are closed we could replicate that, and it would show exactly how bad the backups are going to be," said Lorenzo Rotoli, an engineer and vice president at Fisher Associates, a civil engineering firm in New York that works on roads, bridges and signal systems.