Jim > This is absolutely fascinating to me and is the only explanation for
how it is possible when taking up a paleo diet to increase fat and calorie
intake yet lose weight.

Tom > There could be other reasons. For example, many paleo people say they
feel more energetic. It is easily possible that paleo diets just burn a
little more energy.

That's true.  And there are two other things that I hadn't considered.
First, we've been talking about how the need for salt is greatly
diminished.  I'm sure that there has to be a bit of water weight lost from
that.  Second, there has to be water weight lost too from the elimination
of allergens in non-paleo food.  I noticed almost overnight that my wedding
ring wasn't so tight, that I'd lost quite a bit of puffiness in my face,
etc.  So maybe the weight lost when starting the diet is not entirely fat
loss.  Still, I'm certain that I'm eating more fat now and continue to lose
weight.