I showed up at my mom's house the other night with a wild cardboard aero job and explained I was trying hypermiling. I was surprised to find my mom had heard of hypermiling, and thought it sounded dangerous. I told her I kept the engine on coasting down hills at standard speeds and she said "It still sounds dangerous to me." I didn't delve into that too much because she's not fond of rationality, but it made me wonder if other people think the same thing.
Our highways here are 60mph for trucks, 70mph for cars. I, and many people, do 55 for long distances. In my particular town, I and many other people are a bunch of "goddamn hippies" and do 45-50 with nobody making a fuss. My general strategy is to set cruise for 55, then I'll pulse to 60 at hill crests, and coast down to 50 - assuming nobody is close behind me. I find by doing a +/- 5mph P&G, most of the other 55ers don't have a problem with me at all.
If a semi comes up behind me, I look to see if they can pass safely. If they can't, I speed up to 60. If they can, I stay at 55 until they pass me, then I catch their draft and will go 60 behind them for a while.
Edit: In Washington state, delaying 5 or more vehicles is illegal.
Thank you, Kevlar, for the reality check
