I am a big opponent of our work firearm policy, as it is extremely unsafe. In the Marines (as well as the basic 4 rules), we were taught that our fingers are to be off the trigger unless you are shooting something/someone. Now, my agency has this thing called hot standby, where they want us to release the trigger unneccesarily. We've had a large spate of ND's agency wide, and they wonder why !
The reason for dropping the hammer is three fold:
1. The longarms aren't meant to be carried chambered and the safety, hammer, or sears can all easily fail causing a ND. (I say negligent discharge because the manufacturer and your agency have both instructed you not to carry it that way. Any discharge isn't accidental, it is negligent. It could also cause you to go to jail.)
2. It relieves stress on the weapons.
3. It makes the manual of arms the same.
I know you have been in for a short time, but it wasn't that long ago that even your agency had numerous different shotguns, 870s, 500s, High Standards, Ithacas, and even multiple rifles, ARs, Minis, and even some M14s. Loading the weapons the same way meant that no one had to learn different safety buttons and different slide release buttons. You grab the long arm, then you rack a round in the chamber. You are then ready to deal with any threat. No thinking "is this a High Standard or a Remington?" Even in the HD situation, just being able to rack the round and address the threat is a gross motor function. Fumling around trying to find the action release bar (and/or the safety) is more of a fine motor skill. The former is much more easily done than the latter.
As for the ar, you're wrong about that. Many NDs have occurred from hammer's shearing off, and they are much more likely when bouncing around on rough trails.
Understand that cruiser ready are not just your agency policy they are pretty much standard nationwide for LEOs. Yes, your agency has a funky name for it, but everyone else does pretty much the same thing. I've yet to run into a dept with another policy. There are reason for that.
I know that is pretty harsh. Thought about editing it, but I feel pretty strong about the subject. You are a marine and you carry a badge now. That badge will be respected even more than others because of the traditions associated with it, namely all those esteemed firearms gurus where once wore the same badge.
Stay safe.