All of know is that I drove 3 tanks using the driving with load technique and saw no MPG improvement over my usual climb and coast driving method. Although I don't have a game gauge to monitor fuel flow, I would maintain the same throttle setting I was using on level road as I climbed the hill and went down the other side, allowing my speed to drop on the uphill and rise on the downhill. Of course, I wasn't able to do as much coasting while driving with load since I started the downhill with less speed and did piss off more drivers by going slower over the crest of the hill.

Exel, do your Corolla and MDX have automatic or manual transmissions? My Civic CX has a manual transmission. Perhaps the transmission type may play a role in our differing results.