dnj1965, I loved your dissertation. Thanks! You said it perfectly.
What is the "it" you are looking for?
For me it was appetite control. I simply could not achieve it after what I had done to my body hiking the Pacific Crest Trail for 6 months on a nearly zero protein diet high in simple carbs (candy, cookies and crackers) and crappy vegetable oils (poptarts, fig newtons, cheeze-its, dehydrated cheese-flavored powder, packets of mayo pilfered from gas stations.)
A high fat, low carb diet gave me control over my appetite. I could eat less and lose weight.
Now I'm gaining weight. Weighed on the same scale that said I was 163 a year and a half ago it now reads 142. My home scale said 133 last time I looked (July). My clothes are looser. I eat 2000-2500 calories a day at minimum, a full 500-1000 calories more than My Fitness Pal calculates is my "maintenance."
I'm not sure what "calories" or "weight loss" really is anymore.
Female, 5'3", 50, Max squat: 202.5lbs. Max deadlift: 225 x 3.