Great info, euphoricme; thanks! My experience is similar to yours: I went somewhat off the diet on a vacation to Mexico, and was able to come back much more quickly than I went on. Ditto during a family event last month. What I don't have a good sense of, though, is HOW quickly the recovery now takes: since my usual life is pretty sedentary, I don't know if my return to efficient fat-burning during extended exercise would be an hour or two or a day or two, which obviously makes a big difference in the backcountry.

Of course, the best way to find out will be through experimentation. (Still hoping someone can find a study on this issue -- Google isn't working for me, for once!)

As for pemmican: agreed. I already carry macademia nuts and well-cooked bacon in bags (which if combined might be labeled "Atkins trail mix"), and a vial of olive oil to plain drink. I should look into actual pemmican recipes.

Thanks again!