[comptiger5000]

Pinoslaw - Good point. I hadn't though about the low exhaust temp due to hypermiling. However, for those with larger engines, it might still be viable.

For example, on my Jeep, if I start it on a cold morning, in the time it takes for me to get out of it and walk to the back end immediately after startup, it's already steaming notably out the exhaust. While driving, it steams all the condensation out of the exhaust within 2 miles or so.