What is all this nonsense about mind-muscle? The body is a single machine. The brain controls everything including growth. The brain and the muscle are one. So the trick is to stimulate growth. I can tell you that the requirements for continuous hypertrophy are not for the faint hearted. There has to be a good reason for a large muscle to hypertrophy more. Simply doing more frequency is not the answer but is part of the equation. What is required is a progressively more difficult program and effort. This is where most fall away and are stuck on plateaus.
Ask yourself this: do your muscles have a good reason to grow? There is only one true theory of hypertrophy. It isn't guesswork. It has nothing to do with folklore or beliefs. The methods have been worked out by many huge bodybuilders over the decades. The scientists do not know because they have no interest in the subject so no experiments have been done on champion bodybuilders. To make matters worse, drugs have entered the scene and to tell the truth hardly anyone knows what is responsible for their huge size. Was it the drugs, the training or both? If we eliminate the drugs then we have a chance of finding what really causes hypertrophy. That is what I am interested in. Most Getbiggers literally do not believe that training makes a difference. They believe you need drugs to get huge, but you also need good genetics. Well, tell that to Larry Scott. He didn't have good genetics except perhaps long muscle bellies. The guy invented ways to keep growing. His protocols are painful, extreme, but effective. If you don't grow doing what Larry did then perhaps you should take up table tennis or surfing the internet.
I can tell you that after a few workouts that left my biceps sore I am almost avoiding training them again. Why? Because it is extremely hard work and very painful. If this is what you have to progressively do then it is not something most would continue doing.