This is an aside from a much larger thought process I'm working on.
One of the great strengths of combat sports is that the competitive environment allows people to test their training in a repeatable, measurable fashion. That is a tool with an immense amount of power and value.
If you are a boxing coach, or a boxer, and someone comes in and says, "hey, let me show you this drill that will make you hit 1000 times harder than you already do", you can learn the drill, do it, add it to your training, and see what happens. If your next fight camp has to be focused on bag work and pad work because you've injured all of your sparring partners, and you end the fight by KO in the first round, the drill may have worked. If your sparring partners start laughing and telling your coach not to bother giving them headgear before you spar, the drill may not be doing as much as you'd hoped. Either way, there's a measurable result. You can test the idea, see how it goes, and re-test it.
The fact that sport training and competition offers a method for testing and getting feedback about your training methods is a big part of the reason why a lot of sport practitioners get irritable with facets of the self-defense/traditional crowd. I am, of course, generalizing on a lot of sides here, but as someone who straddles those lines, even I get annoyed when I hear or see someone talking about how their throwing techniques are just SOOOO much more "sophisticated" than those silly Judo guys, or how no BJJ guy could ever tap them.
Because here's the thing. Those arts (and all combat sports) offer a place for you to prove your claim. You truly can't be joint locked? Go enter a grappling tournament and show that you can't be joint locked. You have a punch that is unblockable? Go box, and demonstrate that no one can block your punch.
Now, to be clear: sport training is not the only or ultimate proving ground for each and every thing, and there are some things that don't fit into a sport context. I'm not saying that. What I am saying is that the sport environment is very strong precisely because it does offer those things, and that fact shouldn't be ignored.
Back to the larger thinking...