Adobo
Contributor
Thanks, when I get an insta-buddy I'll remember to do that. So far I've been diving with my better half all the time so we both know who's what and we only do the "half-tank let's turn around and head for the shallows" checking. Now; we used to check more often. (You could say we've grown complacent.)
But that's not my point, my point is there's dive planning and there's disaster recovery planning. I don't plan my dives as disasters because I don't think I'd enjoy that kind of diving. So I think "what if you have to share air when you don't have enough to come up safely" is a straw man argument. If that happens you have a disaster on your hands and need to switch to emergency procedures. Nobody's saying you don't need emergency skills, it's just that your DC's and SPG's normal readouts during your regular dive are not about that.
With that approach, you really don't even need a backup regulator either. If your primary regulator is unusable for whatever reason, you can just go into disaster emergency procedures like CESA or buddy breathing.
The good news for you is, most people go their entire dive careers without ever experiencing a real out of gas situation. So maybe you'll be lucky; perhaps you'll never find yourself wishing that you were sufficiently equipped to handle something as simple as donating to an out of gas diver and knowing that you had enough resources to get to the surface without both of you running out of gas.