Agreed on the difficulty and limited utility of physical checklists for rec diving. As diving becomes more asvanced it’s a great situation for a mnemonic. However, the mnemonic or physical checklist, is only useful if people are trained to use them.
When stressed, rushed, tired, etc people fall back on their habits. If good habits are formed in training those habits will appear at the right time.
If CCR divers aren’t using checklists that already exist is it because they aren’t being trained to use them?
Do they stop using them because they don’t see a positive result from it? If you do something 100 times and you never detect a fault complacency sets in and use drops off?
Do they stop using them because the checklists are overly complicated or excessively long or difficult?
If it’s either of the first two, creating a new checklist is likely to be of little help. Continued reinforcement of the correct behavior is the answer. Peers need to hold each other to the correct procedure. A predive checklist, a mnenonic or physical list, is useful for the advanced and beginning tec level dives I do. They may be excessive for basic OW dives but I still do them every dive and with everyone I dive with. Whether a buddy, instabuddy or as a DM. Leading by example and holding others to the standard is what builds culture. That process needs to start well before a CCR enters the picture.
Sorry, I'm not sure I fully understand, although I do get that you think that checklists should be taught in OW class. Here are my points, to reiterate.
1) A simple, short PRE-JUMP checklist (not to be confused with a build checklist) is a good way of preventing a CCR diver from entering the water without the ability to maintain a PO2 setpoint due to a mechanical issue. This has been shown again and again to be a risk even to experienced CCR divers, and to be lethal without warning (unlike virtually anything that can happen on an OC dive not using a hypoxic mix).
2) Putting this simple little checklist ON your rebreather, in easy sight, so that it can be run down once you are wearing your unit makes it less likely that you will not do it because you didn't bring it, or because you don't want to seem like a newbie clutching one of those little clip on cards. So that's what I'm advocating.
3) This effort - changing the culture to get all CCR divers to use a physical pre-jump checklist - seems doable since we are talking about a very small population of very highly motivated individuals with strong community bonds.
4) While I do insist on three breaths from each regulator while looking at the SPG before getting in the water on OC, I don't see the need for a physical checklist in that case.
5) I can't imagine what it would take to get the vast number of divers getting OW training to start using physical checklists, either at the agency level or at the instructor level. But if you think that is a good campaign to begin (like I'm trying to do with #2 above), then have at it.
6) I think that mnemonics are terrible, in general. The very people who need them most are the ones most likely to misremember them. A physical checklist tells you exactly the same thing even if you are rushed, tired, hung over, sick, distracted or angry. Your brain simply doesn't do that.