> You've hit on the central, infuriating paradox of car-centric cities. We're told that building more roads will bust congestion, but the exact opposite happens

That is a bad reading. If there is more congestion it is because you made some trips that were impossible before possible and so people are better using your city. The point of a city is all the things you can do - otherwise people would live in a rural area with less options but not traffic - so limiting the things people can do means you are a bad city. You need to build enough to get out of this, eventually people will no longer find new/better opportunties opened up by building and congestion will no longer increase (if you don't believe me explain why there is no congestion west of Jamestown ND - an area where few people live that has a 4 lane freeway which by your logic should have congestion anyway).

Note that I'm not advocating you build a road to get ahead of congestion. Generally it is much more cost effective to build a good public transit system. However system is the key here, roads only where because you can get anywhere on them anytime you want to go, if your transit system isn't the same people won't use it.