R2L, when it comes to conditioning, it doesn't matter what you put in a bulldog. It's all about how knowledgeable and skillful a person is. A good conditioner could feed his dog ol'roy from Walmart and have that dog looking like a million bucks. But if an amateur use the same feed, that dog will look like shit and perform like shit.
The better you feed the dog, the less you need to work him. The shittier the feed the harder you have to push the dog to work. A dog's kidneys can only go through so many keeps and punishments.