So not mandatory? That’s strikes me as odd.
Sounds like they treat folks like adults. I've always liked that about that "family" of resorts. I've also seen them shut down "knuckleheads." I like that too. I've always enjoyed diving with RD. Headed back to LC this summer.
I imagine that they try to balance keeping the customer happy and making sure that they have a good trip, while trying to run a safe and efficient operation, but I also have seen the Reef Divers staff (and other DIs on Cayman and elsewhere) take action when a diver acts in an unsafe manner, but they usually do try to treat folks as adults.
I remember once joking and laughing with a DM in Cayman and she said that someday (after she retires) she plans "to come back as a guest and make as much trouble as possible!" so I'm sure that they have seen it all.