There's this other documentary I saw, Forks Over Knives, that propagates a vegan diet, pretty much. And there's actually a really buff UFC champ in there who's a vegan. Supposedly there's protein in plants as well.
Quite a bit, in fact. But you have to learn a little about where it is to be sure of getting enough. If you're vegan rather than veggie, it's harder still, because you have to learn enough to know a little about which amino acids are where to be absolutely sure of getting enough of everything, on average. Doable, of course, but it takes a little light reading around the topic to be sure you know what you're doing.
Sometimes I forget that normal people don't eat like bodybuilders.I can tell you right now that those plans do not contain near enough protein for me to ever consider them.
For an average person, it's probably just about enough I think. If, for example, you work out a lot, or have a high protein requirement for other reasons, obviously that alters the balance. They're designed for the average (moderately sedentary) person I suspect.
