Yes, I think this "formulation" is a great way to make sense of ingredients. But what it doesn't account for is the company making the product. Not all dog companies produce the same quality of food regardless of what is on the label. For example:
"I remember what happened when P&G bought Eukanuba and it wasn't pretty. Quality ingredients being replaced by inferior ingredients, completely unnecessary chemicals and crap kept getting added to the food, the price kept going up and the bag size kept going down."
Procter and Gamble bought Evo, and now I refuse to buy it because I can't trust that its the same quality food that it used to be. Maybe I'm paranoid, but I'd rather be safe than sorry.