[Diesel_Dave]

It's interesting how consumers tend to shoot themselves in the foot concerning FE. A couple years ago I recall sitting in a presentation, where the presenter showed a plot of US model year vs. engine efficiency (1970's or so to present). It was pretty impressive to see how much more efficient the modern engines are.

But then he shown fuel comsumption per mile over the same time period. It was nearly flat! What happened? As the engines were made more efficient, people felt like they could now "afford" a heavier, more powerful vehicle (think SUV), that was more efficient (thermodynamically speaking), but got about the same mileage.

Interesting how consumers "feed back" on changes in technology!