I'm sorry, but this is just a load of bollocks. There is a fundamental difference between public transport and cars, other than the upfront investment that was pointed out in another comment: A car is a ~12m2 sized thing that you have to (a) somehow route into the system (road space requirements) and (b) leave somewhere when you do your business.

(a) is an overhead of a factor of ~40 compared to people standing and a factor or ~20 compared to people sitting for the transport alone (I'm assuming here people driving alone, which from experience is how this mostly works out).

(b) is an additional constant overhead of 12m2 for every participant that's not moving.

In computer science terms, your network protocol sucks, and leads to inefficient cities.

Would you like an example? L.A. metro area has about the same size as Greater Tokyo, produces about the same amount of carbon emissions total (!) [5], yet provides space for 2.5x less people and produces ~2.4x less GDP at purchase power parity [1],[2],[3],[4].

[1] http://en.wikipedia.org/wiki/List_of_U.S._metropolitan_areas...

[2] http://en.wikipedia.org/wiki/Los_Angeles_metropolitan_area

[3] http://en.wikipedia.org/wiki/Greater_Tokyo_Area

[4] http://en.wikipedia.org/wiki/List_of_cities_by_GDP

[5] http://www.researchgate.net/publication/223399559_Twelve_met...