A Tango fits in half of a lane with more clearance on each side than a truck or bus has in a full lane. This is true for standard 12-foot wide lanes, but is even more true for the 10-foot wide lanes found in many high density urban areas.
More sociable: As both sides of the Tango are the driver's side, no need to talk across the passenger seats.
Even when staggered, providing additional safety, lane capacity is still more than doubled. Watching a pack of motorcycles on the freeway further proves this point, although in a Tango, one would be more comfortable in even closer proximity to another Tango or car because of the protection and superior instantaneous agility over a motorcycle(because of no need to countersteer).
A perfect size car for what people need 90% of the time, whether for personal ownership or as an option for a car share program.
The parking space in from of the Auckland, New Zealand City Hall, accommodates 4 standard cars, or easily fits 16 Tangos. Imagine the convenience for car sharing, and ease of parking.
Any color you want.
Filtering is legal for motorcycles, many of which are much wider than a Tango, in many parts of the world, including California. New South Wales, Australia just passed a law allowing filtering at up to 30 kph. This shows how there is beginning to be an understanding of the benefits of filtering for both traffic congestion and safety. Many studies have now shown that it's safer for motorcycles to be between the cars rather than driving in queue.
 “The significant problems we face cannot be solved by the same level of thinking that created them.” “The formulation of the problem is often more essential than its solution, which may be merely a matter of mathematical or experimental skill.” “If I had an hour to solve a problem I'd spend 55 minutes thinking about the problem and 5 minutes thinking about solutions.” ― Albert Einstein

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