Excellent summary, KC. One thing I'd like to comment on, since the concern of lactose intolerance has come up:
It doesn't really work that way with regular food portions, and would require more preparation and probably more cost as well. That's probably the final point that really adds to milk's case. The efficacy of cost. The highest I've seen a regular gallon of milk is 3 dollars. At first, people new to the idea say "holy crap, that's way too much for me to afford 1 a day."
Soon they realize that trying take in that same amount of food, especially with that kind of quality, will probably cost a whole lot more.
The cheapest I've seen lactose-free milk around here is around $3.00 for half a gallon, which is also the largest size in which it is available here. This at least doubles the cost of milk if one is doing GOMAD or a variant thereof. While it is true that it still has a good cost-to-calorie ratio, many people view GOMAD as
supplemental. That is, even if they consciously realize they need to ingest tons and tons of calories, they see the gallon as on top of what they'd eat anyway. So the caloric losses due to not drinking the gallon aren't nearly offset by the extra food one would eat instead. Therefore, it's still cheaper, in reality, to drop GOMAD, since you won't be trying to get the same amount of calories.
EDIT: Mind you, I'm not advocating this viewpoint. However, I feel that this is a practicality that one must consider when evaluating the adherence to the program.
