I have read the ERFYBT book and while I don't agree with everything it says or the Science its based on, I have found some of the theories useful and correct. As a type O I know from experience that I do not tolerate grains well, although I crave them above all other things. I also realized why my efforts at being 100% vegetarian have failed because after a couple of months I get extremely weak. Apparently type Os need some form of meat, no matter what our philosophical preference might be. I even got weak while eating Boca burgers before I found the truth about too much soy.
Rather than blindly following any of the blood type, Ayurvedic, or metabolic type diets, I just use them for a simple guideline and self experiment to see what works for me. For best results I have discovered I must restrict grains, eat plenty of green vegetables, have some form of meat a couple of times a weak, and limit sweet fruits. I think our bodies will let us know what they need if we can separate our fleshly appetites from our body's innate knowledge.
I admit I'm far from perfect. On Tuesday at work we are having a catered meal of the best Barbeque south of Kansas City and while I won't be a glutton, I do plan on enjoying the treat. The hard part for me is giving in to emotional eating.
As far as coconut oil being an "avoid", don't you think that may be because for years we have been told to avoid coconut oil since its a saturated plant based fat? We were told that Canola was the best and just the opposite is true. It seems the really bad oils and fats are those that are the result of man made experimentation like Canola oil and transfats. Sometimes things are just taken for granted and thought to be true without really researching the facts.