I have heard that there is a way to set your long term trim levels so that you can get better mileage in open loop than in closed loop. On my Saturn, there are about three or four throttle settings/ranges that the trim can be set for. Idle, foot barely touching throttle, cruise, and just below WOT. I tried to do this once and I didn't have much success. :-( I either didn't follow directions right or my car is right for the method.
Horsepower is how hard you hit the wall, torque is how much of the wall you take with you.