It's not all they do at the TBR. There is definitely good instruction. But, pretty much anything is all about the work you put in afterwards. They even say at the camp that the most important day is the day after the camp ends. You need to put what you learn into play. You can't change anything instantly. Too often I find people looking for quick velo fixes, etc. In my experience as a dad of a pitcher who throws 90+ mph and a HS baseball coach, I've come to the conclusion that there's no such thing as a quick fix. Improvements are almost always gradual. Every pitcher who comes to me and says "Oh, I figured it out...now I throw harder, watch!" is always disappointed when they see their velo on a gun. You have to focus on getting a little bit better every day and putting the time in. Get velo quick schemes are the baseball equivalent to Get Rich Quick schemes. You have to put countless hours in.
Driveline's HTKC is extremely detailed with drills, information, arm care, strength/conditioning/training, etc. In my experience, it's the most comprehensive information on gaining velo. But it's worthless if you don't put a ton of work.
I know the NPA's work, but haven't used it much. I would rank it a lot lower on the spectrum. I'm sure others have a better opinion of it. I can tell you that, IMO, there's no way they've put in as much "Science" as Driveline, who has their own lab with trackman, several guns, many different recover modalities, etc.
Again, all my opinion. I'm just one person who's tried a lot of stuff and figured things out through trial and error...and am still learning.