This post isn't meant to support or contradict LCHF diets. I just want to point out a detail.
Calories in equals calories out is a misleading statement. Calories can be burned, stored, or excreted. Drugs like Farxiga prevent glucose absorption by the kidneys, so a portion of the carbs you eat (calories in) just get peed out (calories out).
Simplifying eating and exercise with the statement "calories in equals calories out" isn't really as meaningful as people imply. People who say it usually mean that if you eat X calories, you have to burn X calories to avoid storing some, but in reality you can burn less than X calories and excrete the rest and still stay neutral. Many things can effect how many calories our body excretes rather than stores.
No. You've given exactly one example: a drug. In fact, there is very little variation from person to person in proportion of dietary calories that are excreted, and the calorie contents of foods reported in nutrition tables and nutrition labels—called physiologic energy—are net of the excreted calories anyway. So the equation, calories in = calories burned + calories stored, is extremely accurate, given that the "calories in" value is physiologic energy.
That may be. As a Type I Diabetic, I have a warped perception of this since I can control how much glucose my body absorbs in a very direct way* via insulin. Carry on.
*: I control it as my doctor directs unless I accidentally mess up, so don't think I'm running a high blood glucose to try to lose weight. I'd just end up eating more, staying the same weight, and screwing up all my capillaries in the process.