Between our High Gear Media sites, we've driven a number of Golf and Jetta models with Volkswagen's 2.0-liter TDI clean-diesel engine.

And in past driving experiences with the Jetta TDI, it's been tough not to be rather fixated on achieving top fuel economy results—as it is one of the highest-mileage non-hybrid vehicles in the U.S. market.

About a year ago, a test Jetta TDI achieved 43 mpg in a very conservative, economy-minded driving loop in a manual-transmission Jetta TDI sedan—and 36 mpg altogether in commuting-style conditions.

But this time, to heck with it. The 2010 Jetta Sportwagen TDI was driven on short trips, keeping pace or faster than the flow of traffic, making jackrabbit starts, and avoiding the vigilant speed control and mindful coasting that many green-car drivers practice.

Besides, all that torque (up to 236 pound-feet of it) can be a lot of fun. Did you know that you can peel out in the TDI quite spectacularly?

And we still, by the end of the week and about 100 miles, had averaged 32.6 mpg according to the trip computer.

As we've previously reported, you're likely to quite easily meet or exceed the EPA's fuel economy ratings for the Jetta TDI in real-world driving. And the exercise highlighted one of the real strengths of diesels—that you can simply drive them like normal cars. You don't have to pulse and glide (dedicated hypermilers know what we're talking about), fret about technique, or drive like there's an egg between your foot and the accelerator to get quite impressive mileage. That, and the excellent DSG automated manual gearbox makes the TDI feel sportier than a conventional automatic would.

With most hybrid models—and the 2010 Toyota Prius is certainly no exception—pay no regard to the power flow, run those accessories, or take off too quickly from stoplights and your mileage will deteriorate significantly.

It's worth considering what level of discipline you have. If you want to choose a greener vehicle but are going to be too impatient to drive hybrid-style, a diesel might be the right choice.