Rationale.............on a thread like this is an odd question.
First I have experimented on myself for years now. I did cure my thyroid and adrenals by eating whole foods and getting rid of the alergens that were causing my body to attack itself. I am still leary of eating the things that caused the problems in the first place but am not going to sit back and hope my body gets better by not doing anything. I was gaining weight very rapidly when I found out I could not tolerate alot of foods. I stopped eating those foods and started feeling tons better. I still was over weight and could not lose it for anything. Enter Primal blueprint. Which did not work for me on it's own. So a few months in I started paying attention to my lethargy and my eating habits. I would eat breakfast and get really sleepy. Then comes lunch and sleep and serious issues thinking straight. So I started reading the threads on intermittent fasting and Pklopps info and it made sense. I tried it while closely monitoring my temps. If they didn't go up from the 96 to 97 average they were at then I would know that it wasn't helping. Same goes for the adrenals. Only I monitor them by how much my temps fluctuate. If it's more that 3 degrees differenc on average for 3 consecutive days then I know my adrenals are struggling. I am at heart a self experimenter. That is truly where most of my rationale comes from. The potato feast is just another addition as my temps have leveled off and so has my weight loss. So I move on to a new experiment.
Plus just like you I have people I haven't seen in a long time coming and I want to look my best.
Just because I have these endo diseases does not mean I have to settle for fat and boring........
P.S. and as far as the calorie restricting that is only on this potato feast and because I can't eat anymore than about 800 to 900 calories of them(if I'm lucky). I normally do not ever calorie restrict and am avidly against it. That is why it took me this long to try the feast.