Whoa, guy, are you suggesting that regular practice trumps the differences between disciplines?
The US Air Force Security Forces (Air Force military police) teaches a combatives curriculum that is virtually all BJJ. I take issue with it. That's not to say I take issue with BJJ... it has saved my life, so I have a special place for it in my heart. But, when you consider that many defenders (USAF security forces) will take two weeks of combatives in the academy, do a refresher once or twice yearly, and that's IT, I believe BJJ is way too complicated to be the basis of the system. Now, we can argue that they should train more REGARDLESS of the system (I've said it many times), but, the fact is that someone can become decently proficient in throwing punches, blocks, and low kicks with two weeks of defensive training. That's not to say they will be able to throw a punch with the brutal efficiency of a 3rd dan in Shotokan, but they can probably stand their own against a drunk or an irate cyber nerd, which is generally what an USAF cop needs to be able to do. BJJ is more nuanced, and I'd argue you need considerably more time to develop even a semblance of proficiency. Moreover, BJJ trains in conditions that are vastly different from the real world. True, all martial arts do, but the fact that I'm wearing a plate carrier with level II or III plates, a baton, a Beretta 92, possibly an M4 assault rifle, and ammo for the aforementioned weapons, the dynamics of fighting on the ground become very different. I can throw a punch with all that gear on... I can't say the same for a triangle, nor can I say I'd definitely want to, given where a triangle may place my holster relative to the suspect. Finally, given the realities of real-world fighting, as a military LEO, I don't want my primary defensive system to be so ground heavy... you don't have to worry about your suspect's buddy kicking you in the head when you're in a controlled environment.
I'd be interested to see what [Kemposhot] thinks about this, as he is an actual cop!