Control is not about the teachings, it is about the concept that they are a special people. I think the GB are becoming more aware of that, and so have cut back on heavy doctrine, and now push more the idea that they are the chosen ones, and there are no one else on earth like JWs. The doctrine are basically just filler to make the religion look legitimate.
Reminds me of how pedophiles lure and confuse the victim by giving them attention and making them feel special, except the WTS does it on a larger scale. It's pretty sick.