I'm not sure I buy some/all of their reasoning. They seem to have a one scale fits all way of looking at the foods. I think this is a case where the buyer has to be aware of the needs of their breed as well as the "score" of the food.
Eagle Pack Holistic foods only rate a 4, and the reasons given seem to be "Insufficient meat content" and "Beep Pulp".
Well . . . the whole point of this food is keep the protein content in the mid-20s, so the "meat content" is NOT insufficient if you're trying to keep your giant breed dog from bursting out of it's skin with HOD and other rapid growth ailments (as just happened to a mastiff pup my two play with; his mom had him on Orijen large puppy [which rates a 6], which is a great food, but at 42% protein is NOT ideal for a mastiff or other giant breed*).
As to beet pulp, as far as I know, the myth that it is bad for dogs has generally been debunked, and the benefits for omnivores of all kinds (including humans) is pretty well accepted.
*The website does spell out that the food is not in fact suitable for puppies, but they still give a “6” to a product that’s name and major claim/purpose they disagree with. This seems more than a bit problematic to me.
There has been a study done on whether protein contest actually makes puppies grow faster and shown that it's not. The calorie intake and not sufficient exercise what makes them grow and cause orthopedic issues. http://www.dogresources.com/phpBB2/viewtopic.php?p=1002&sid=c540e4a6a86965f067fc6709b42d8258
The concept explained on dogfoodproject as well. http://www.dogfoodproject.com/index.php?page=protein