All of the major freeway expansions I have experienced required at least two years to complete. During these periods, lanes in the construction zone were heavily constricted, resulting in all of the roads surrounding the expansion project being completely filled with stop-and-go traffic during peak hours until the projects were completed, which seems to suggest the number of lanes makes some kind of a difference in something, somehow.

The authors seem to suggest that demand for roads is infinite, as expanding roads merely increases the number of trips people choose to make, thus infinite expansion will result in infinite trips.

These analyses always appear to me as if they are without any understanding of how humans actually behave, resulting in nonsensical nonsense "laws".

One of the reasons why this keeps getting executed is that there is a latency between added capacity and induced demand. So you can 'solve' traffic temporary just around the next election.

I have a lot of trouble believing the premise that road capacity is unrelated to congestion. Practically we know that road capacity is only increased when congestion reaches critical levels. We also know that there are some massive empty roads that no one magically came to fill (as shown on Top Gear). Anyone who has lived in an urban area knows that congestion increases over time, whether they add new roads or not.

> Overall, VKT in the US doubled from 1983 to 2003, from 7,700 VKT to 15,900 VKT for interstate highways. For major urban roads, a similar pattern occurred – VKT went up from 15,000 to 30,000. In the same time span, the number of lane kilometers of interstate highways remained basically constant, while on major urban roads, it went up from 3,800km to 6,500km.

I don’t know how someone can trot out this stat and then claim with a straight face that new lanes cause congestion. What this states is that car traffic doubled over a 20 year period, and it doubled whether lane capacity increased (cities) or not (interstates).