I'm not necessarily telling people to go strictly 80-10-10, but to go in that direction and from there it's their choice how far to go.
But as to the dangers of 811, I've researched it quite a bit and the only real danger with it as far as I could tell is not meeting your minimum calorie requirements. Then one will start to coming down with signs of malnourishment (hair loss, brittle nails, dry skin, fatigue, moodiness, severe weight loss, teeth & gum problems, etc).
Also, lots of people say they are on a certain type of diet, but really aren't.