There's actually some science behind this diet. Potatoes are the highest scoring food on the satiety index. https://www.healthline.com/nutrition/15-incredibly-filling-f... Basically they're the most filling food per calorie. So if you subscribe to the idea that losing weight is mainly about how many calories you consume, a potato heavy diet should be effective. And an all potato diet, while monomaniacal, even more ef…
Potatoes are more filling per calorie than broccoli? Spinach? Also I wonder the comparison between potatoes and protein champions like hard-boiled eggs or fish. Maybe we could have a nice American eating competition to compare. Or just a detailed study where people eat short-term diets of each and measure their satiety and other vitals.
Way, way, way more filling. Regular vegetables have basically no fill value at all. Just a fancy form of water & vitamins. Potatoes are quite good at filling.