It's 100% observable. I used to work for a regional transportation council that made high level decisions for where to alleviate congestion. There were many hun

It's 100% observable. I used to work for a regional transportation council that made high level decisions for where to alleviate congestion. There were many hundred-million dollar projects that counterintuitively increased congestion, because the increased availability created by the infrastructure caused even more people to move to the area. After the original project was completed, decreased congestion would be observed, but 2-3 years later it would be even more congested than before the project began.