Finny, you get weak and pudgy because you are not getting adequate protein. You were also losing muscle mass which uses calories at a more rapid rate than fat and some other tissues.
Exactly. Same amount of calories taken in -- but from different sources, so different outcome in caloric burn -- lean and vital when the calories burned come from one kind of food, weak and pudgy when they come from another kind of food.
It is true -- someone who is fat quite simply is ingesting more calories than he/she is using up. That is simple and that is TRUE.
Sure, if you burn more calories than you eat, you're going to lose weight. But that is not a daily model for living and never will be, carefully balancing calories in versus calories the same as balancing a checkbook. Efficient use of calories is crucial; calories may be "the same" in burn calculations, but they are as different in the real results as the food sources they represent in terms of nutrition.
Straight "calories-in-calories-out" computations are a deeply flawed way to loose weight. You have to RESPECT that the body is a biological machine in which the TYPE of calories in dramatically effect the QUALITY and RESULTS of calories burned via exercise.