Your point is very important, I think. My daughter just completed her university open water scuba course. At no time during the semester-long course do the students use an AIR 2 (nor an octopus, nor a power inflator)--even though the gear that the students use for their open water checkout almost always includes an AIR 2!The problem is trying to use it as a regulator, while also maintaining buoyancy (adding/dumping BCD air). It's a skill you can easily self-teach and practice. Divers often think "it's just merging the inflator hose and octo" and don't realize they need to practice, and then have increased difficulties in an emergency.
I did a gear checkout (full open water gear) with my daughter in the pool a couple of days before she left for her open water checkout. I had already introduced her to the AIR 2 earlier, at home, in the living room. However, we spent some time practicing with the AIR 2 in the pool during our gear checkout.
I cautioned my daughter, before she left for her open water checkout, that we hadn't practiced enough to make using the AIR 2 "instinctive", and that she needed to practice using it a lot more.
rx7diver