"The problem is not too many single-occupant drivers. It's the design of the cars that they are driving."
Putting all discussion of solutions aside, this strikes me as naive. Including this quote on the same page as "The significant problems we face cannot be solved by the same level of thinking that created them." is ridiculous. Highways would still be crowded even if everyone switched to the Tango, and fixing that requires more than a smaller car.
"The fact is: People who can afford cars will use them, despite the inconvenience of traffic congestion."
This is another point they make that I don't agree with. Commuters will choose their mode of transportation based on comfort, speed and affordability. If another mode of transport rivals the car on these points people will commute less by car. Making this point only goes to show that the people behind the product are locked in a car-centric mindset and that the idea of commuting by train is off the table before it is even discussed.
Highway congestion will stay with us as long as cars are the only viable option for commuting, and as long as suburbian sprawl goes on, that will be the case. Even if the cars get smaller.