Phoenix is proud to open it's first 22 miles of electirfied light rail this weekend. There will be more to come.

Focusing on transport efficiency ignores the larger externalities, both pro and con. Infrastructure differences, durability, funding approaches, community layout aspects, housing impacts, and developmental focus are very significant.

If we didn't have roads between buildings, would we have covered sidewalks for inclement weather and sunny promenades for nice weather walking? Would we have a train station at the indoor malls and event centers? Would we have indoor parking for suburban park-and-rides? What would a suburban neighborhood look like without streets and driveways? How would you bring home a new TV or sofa, or a pool or fence? Would the notion of front-yards and back-yards change, with gravel alleys in the back versus curbed streets in the front?

Total cost and convenience seem to me to be the base factors for consideration, though changes to the status quo are important too. Of course many cost factors are invisible (what's the visibility of garage and driveway costs in an analysis of auto-lifestyle TCO?), and others are blurred (would I rather pay more taxes for a nice bus/train solution versus the monthly personal costs/savings in auto and insurance?).

What we need is some "planned societies" that provide workable examples of a transit-oriented lifestyle. Not just a vacation village somewhere, but a real working city with active construction, residential neighborhoods, manufacturing and warehouse districts, entertainment, professional workplaces, grocery stores, and shopping. Is there one in the first world with no personal car traffic at all?