I live on top of a hill with a bit under two miles of pretty steep grades to get between home and to the freeway. Coming home, I have to climb to the top of the hill, then go back down a rather long cul de sac to the house, so each trip is up and down. What I usually do is get up to speed on the flat part at the base, in some cases requiring somewhat of a "jackrabbit" start because there is a stop light, a short flat part, then a climb, but I've actually averaged a bit better doing this than trying to accelerate while climbing, steadily. Unfortunately, the trip up and down has lots of stop signs, and lots of very sharp turns. This forces me both to drive much slower than would be good for fuel economy, in addition to requiring myself to stop and start often. Going down, I can never maintain momentum for very long either, thanks to the stopsigns.

What I usually do going up is get up to speed, a bit faster than the speed limit, then as I go up, lose speed on the steep parts, and regain it a bit on the flatter parts. I also allow myself to coast up to the stops in such a way I don't even need to use the brakes at all. I've also gotten good at taking each turn as wide and as fast as safely possible, so as to conserve momentum. Finally, I feather the throttle so that the FE is as high as possible, while still delivering "assist." By the time I crest the hill, my battery is close to empty, and I can recharge it a fair amount coasting back to the house.

Going down, I do the following: Shift the car into "S" to control speed (I drive a CVT, not a manual), while still tapping on the brakes just enough so that it kicks in all the regen braking without 'riding' the regular brakes. In addition, I run the air-conditional all-out while going downhill, It actually helps me brake, and it gets the coils nice and cool before I begin my normal drive. Later, when I get on the freeway, I can turn the thermostat to a higher temperature, or switch to fan only.

Since I optimized my semi-daily hill climb routine, I've found my FE has been helped very, very dramatically. For a straight "up and down" trip among the more forgiving routes, I average about 36mpg. That's better than most typical cars average on the whole, and only slightly worse than some lifetime averages for the HCH itself. I average just under 52 overall, even with a lot of short trips (I'm thinking it's time to pump up the tires, they're starting to get a bit too "cushy" for my tastes...)