Measuring traffic efficiency

The Texas Transportation Institute put out a report in which they measured road efficiency by comparing travel times/mile. Yglesias objected here, and the Greater Washington Blog objected here. CEOs for cities measured time on the road for commutes here. 

 The objections are wrong, they attempt to measure sprawl, not traffic efficiency.  The correct measure of traffic efficiency, time/mile.  Sprawl is a separate study, which one can obtain from the CEOs for Cities.  Why do the two objectors want to mix sprawl with a traffic efficiency study?  Sprawl has more cause and effect than just traffic, it is an aggregate measure designed to support government planning, especially transit.  Transit advocates  cheat, using data manipulation to get a result they want. If we could get the number, the best useful measure is lifecycle energy cost/mile, that is the measure that Antiplanner tries to get at.

Matthew Kahn weighs in regarding the Bay Area commute.  He compares the state run Caltrain with the parralle freeway 280.  He gets half the problem solved with road pricing then creates worse problems with subsidies

Institute road pricing on the 280 Highway and earmark 15% of the revenue collected to Caltrain

Why not just do the road pricing and leave it at that? Matt pays lip service to lifecycle cost/mile or Caltrain, but he shouldn't do that if he wants subsidies, he has no idea what is being subsidized.  Road pricing alone should force the competition between fast buses and Caltrain.  Allow variable road pricing and bus riders can actually get service that is faster than car or train.