I would vouch for what Hound Dog Mom has to say. She knows her stuff. Seriously go to the Diet and Health Issues forum and look at the first topic there about Large and Giant Breed Nutrition. You will find ALL your answers in that topic. I know I did.
My breeder also suggested a low protein diet and extra calcium to fix my dogs crooked leg. Turns out I was feeding a diet much to high in calcium and in doing more research on the calcium issue learned that it is the high calcium that causes most issues. Not the protein. Took him to the vet, got a splint right off the bat, took splint off in 4 days, completely fixed his leg. Haven’t had an issue since switching his food and getting that splint.
