"Exponentially diminishing collective returns"

The New York Times is hosting a discussion on the somewhat over-hyped distinction it has drawn between European cities supposedly out to make motorists' lives a misery and American cities which are not. I like Tom Vanderbilt's contribution best, as I think it puts the idea that cities should be remade around cars in its proper historical place:

The idea that a city like New York could be made wholly compatible with the car looks increasingly antique, a paved-with-good-intentions fever dream now as obsolete as the idea of tower-block housing projects. As Michael Frumin, a transportation expert, once observed, if the morning subway commute were to be conducted by car, we would need 84 Queens Midtown Tunnels, 76 Brooklyn Bridges or 200 Fifth Avenues.

The car, with its exponentially diminishing collective returns — for example, traffic — is not the solution to mobility in the increasingly crowded cities of the 21st century. The sooner we put this flat-earth belief behind us, the faster we can get along with ideas for more efficient forms of mobility.

I love that phrase - exponentially diminishing collective returns!