I don't disagree with any of that--I certainly do find it easier to fast if I first eat at a very ketogenic level for at least a day or two, and calorie restriction with a high carb diet led to relapses with higher highs year after year. I might have eaten less calories on low carb, I don't really know because I didn't keep track, but one way or the other it didn't seem like less. But whether these young guys would have done okay on low carb--I don't know, it's likely they might have felt better early on, once they got past the carb flu but before they had lost much of their fat stores. It's hard to say that they exactly spared their fat tissue, so really you'd have to assume that they'd have burned less calories over the course of the experiment, otherwise you'd just be looking at the order in which fat and lean were used up--maybe they'd have started panicking a little later then, I don't know. Cahill did a study extended fasting lean young male students, they were burning about 1100 calories a day, so maybe with 1600 calories a day of a low carb diet, they could have gone on indefinitely, even with the exercise.