Even if the diet works, I'm having a hard time with the set point theory. First, a couple of lame objections, and then an alternative theory.
Lame Objection 1:
I've been gaining weight since I was 18. Then I was about 150lbs. Now I'm 300lbs. My average daily excess in calories is about 50 (a mere Oreo or thereabouts!). So if I have a set point, what is it? A jillion pounds?
Lame Objection 2:
If the "point" that is "set" is body weight, then why wouldn't wearing an appropriately heavy overcoat or weight jacket stop weight loss? The obvious answer is that it must be something (or things) more subtle that gets "set". What then?
Alternative theory -- calorie miscalculation by our brains
The fundamental problem for our brains is that they cannot directly assess the calorific and nutritional values of food merely by looking at it. As a result we have evolved "proxies" for those values, the most important of which include taste/flavor, mouth feel, smell, and so on. In other words, the things we experience when we *eat*. For some reason, the brains of some of us miscalculate based on those proxies. To get around that, something like intravenous (or nasal) feeding could be used, so we don't rely on the proxies. As Seth mentions in the book, an experiment with nasal feeding did indeed show the desired effect. THUS, SLD is not affecting set point. It is affecting (correcting) our brain's calculation of how much food to eat. It could be argued that that *is* set point, but crucially I'm saying the effect is a *per meal* effect.