Earlier quoted context omitted.
The Atkin's theory, which I believe has been largely substantiated, is that carbohydrates (sugar, HFCS) do not satisfy hunger, they tend to trigger hunger. John cut out the sugar and his hunger dropped. FWIIW, my experience was the same and there are many others who echo this. See "Sugar: The Bitter Truth" (UCSF lecture) which goes into detail on the metabolism of carbohydrates, especially HFCS http://www.youtube.com…
You have to say specifically "carbohydrate" and not single out sugar. People try to make this false distinction between "complex" and simple carbohydrates and sugar. ANY starch is broken down rapidly in the small intestine and absorbed as sugar.
That may be an oversimplification. Lustig, in the lecture mentioned by the GP, shows that there are big differences between how the body metabolizes glucose and fructose. If these differences are significant enough (Lustig's thesis is that they are), then it isn't a "false distinction" to single out sugar/HFCS from other carbohydrates.