[firedaemon]

Mostly I think the idea of induced demand should encourage us to increase the availability of transportation in “novel” ways as opposed to just adding more road. You can add more road forever and just get more traffic. If instead you add rail, say, you satisfy demand and avoid a concrete highway hellscape.

[autoexec]

I 100% agree. Too often though it's used as an excuse to not update roadways in places where there are zero efforts being made to introduce new public transportation.

It's also worth noting that induced demand exists even for public transportation systems. A single rail line can solve the bandwidth problem for a longer time than a new lane on a highway, but if growth continues you'll still end up needing to add new trains and rail lines or add additional modes of mass transportation.

Induced demand is never a reason to leave the problem of bad infrastructure unaddressed, it's just something we have to take into account as we try to improve things.

[NeoTar]

There were suggestions (pre-Covid) that the Elizabeth line, which increased east-west capacity in London by some ridiculous figure (over 50% if I recall correctly) could be saturated by induced demand (or if you prefer the realisation of suppressed demand) within six months of opening.

[marcosdumay]

Those also have the same induced demand effect people are talking about. It's just that they can absorb a lot more usage than roads.

Adding a passenger rail is in principle not very different from adding a 10-lane corridor. Including the problems of what those people do to enter or leave it, and the fact that it too can become overloaded.

That said, yes, of course the rail is a much better option.