I don't know anything about any theories of weight loss.. but I do have experience with yo- yoing! As someone who has struggled with eating disorders I can tell you that it is possible to screw up your metabolism by the yo yo dieting. I also know that people who only have 20 pounds or less to lose will not drop as fast as those who have more than that,because they are closer to their ideal weight. In Atkins he says that what you BELIEVE is your personal IDEAL weight is not necessarily what your BODY will . In other words, I want to weigh 135,but I may stop losing at 150. This does not mean that you can't lose more, just that you'll have to adjust your carbs accordingly until you begin losing again. I don't know if that helped at all. But I do know I really screwed my metabolism up by dieting.