PT146 · S1 · Q17 In order to relieve traffic congestion

If most downtown workers are commuting from the 'burbs, then the effect of the new highway should be making their lives / commutes better. After all, the highway's purpose was to better link suburbs to downtown. So this answer makes us even more confused how commute time has gotten worse for these workers.

The fact that the highway is most convenient to people in the largest suburbs means that we can expect a lot of people will want to use this new highway. That should decrease traffic congestion on the roads people used to use to get from suburbs to downtown, and thus commuting times should be going down. This doesn't give us any reason to explain why commuting got worse for downtown workers. It seems to either not have anything to with them, or it sounds like it's a positive for them.

This is a tempting answer for a lot of us, because it shows something else that's changed since the highway was opened, and the idea of new stoplights sounds like something that could explain increased commuting time. But it sounds from the phrase upgraded with new stoplights like these intersections already had stoplights, and those were swapped out and replaced with new ones. In order for commuting time to be made worse, we want to believe that there used to be no stoplight at an intersection, and now there is one. But replacing a stoplight with an upgraded, new one doesn't have any common sense connection to slowing down traffic flow.

This is talking about stuff prior to the highway opening (when it was still being built). We're looking for something else that changed once the highway opened.