I feed this too along with tinned butchers tripe. A lot of processed dog foods contain too much protein, salt and sugars. I know many folk in the dog world who feed bakers dog food if they have an underweight dogs as bakers makes dogs fat.
I don't think its possible to feed too much protein, but easily possible to feed too much poor quality protein, leather shoes are indeed protein after all. Raw meat is about 20-30% protein. Some dry food manufacturers claim high amounts but it may not be digestible. When I fed dry food I used Arden Grange but if I,were to feed it now I would feed Orijen.
As you point out salt and sugar and completely unnecessary in a dogs diet and are only added to make the food palatable, so when you try the dog on an alternate healthier food , they refuse it, much like a child who is spoilt with sweeties being offered a vegetable instead. My only issue with James Well Beloved mentioned above is that they add salt.
Bakers is a complete no-no, it contains additives linked with human ADHD and Cancer. It actually harms your dogs health.
I'm not sure about the food type causing or eliminating pee burns in grass as it is simply ammonia that causes the burns which is always presents in a dogs pee (ammonia is something we know about here
😉 ). Bitches tend to cause more than dogs as they pee in a puddle whereas dogs will cock their legs, typically against something so the burn patch is smaller as it is mostly reflected spray.