"Proper" gas planning, 3rds, do take into account catastrophic failures and are used more frequently in situations where you absolutely need the buffer (caves, wrecks, very deep, etc). The average rec diver is using a turn pressure of about 1/2 with a plan to return in the 500-750 range. A critical failure (incident if you had a pony) is now an emergency. Dark, cold, snowy waters and your 6ft of separation is enough to cause problems. Having a redundant air source gives you time to address most problems while you either 1) get to your buddy and begin sharing back gas or 2) signal and surface while not being tethered to your buddy
In my opinion, there's nothing magical about any fraction. Proper gas planning will depend on the circumstances, and just diving 3rds is not it. There are probably many valid ways of doing it, but it should account for gas sharing in an emergency from the deepest/furthest point in the dive. Call it "rock bottom" or "usable gas" or whatever, the point is to have an appropriate gas reserve for the dive. The rest of the gas you can use as you see fit. If you "must return to the starting point at all costs" then you need to at least dive 3rds on top of the reserve and take into account that your buddy might need more air than you, is there current, other obstacles etc.
As you describe it, the average Rec diver is not using proper gas planning. I think they should. Let's leave it at that.
I agree that having redundancy is an advantage on more advanced/deeper dives. I just think for a lot of rec divers "just adding a pony" might not make them any safer, and for some it might even contribute to giving them a false sense of security or pushing their limits instead of taking steps to learn to be a better/safer diver. This is obviously not true for everyone that uses a pony, but I do think it happens.
When I dive I'm not going to babysit a shịtty partner unless they're my family. I dive so I can go see what I want. I'm often on a scooter and now that I have my own it will be even more so. We're all down there to float and be away from people.
Fair enough, then you're solo diving. Do as you wish. My point is that if you have that mentality, it's quite ironic to complain about buddies not being reliable and that it's easy to get separated. (Not that you did, but I hear that sentiment from a lot of posters that seem to blame others for their lack of buddy communication skills).
If your profile is correct, you only have a few to several dozen dives. Do hundreds more dives, with different characters in varying conditions of current, visibility and dive objectives and you will almost assuredly look up and see nobody around you. Generally you should have a good idea which way to begin to look, but still sheet happens. Have you ever had a buddy panic and bail or have an equipment problem and just leave? It will happen sooner or later.
Agreed, I'm still quite inexperienced, and maybe my perspective will shift as I gain more experience. However, after 90+ dives in cold black/green water with visibility ranging 2-30ft and tidal currents, I still think it would take a lot to get separated from me. Mostly because if I don't trust my buddy, I don't let them out of my sight. I've had a few people pop to the surface towards the end of the dive or during ascent, but I was aware that it happened and found them on the surface. Now, I did have an instructor sneak up behind me while I was focused on my team mate doing drills, so of course it is possible to lose track of someone if they deliberately try to lose you - especially if you trust them and they're not really your team mate.
By the way, I appreciate you sharing your story and also the way you responded to my question. It was not meant as a dig towards you.
Also, what activities are you doing during a dive? What are your goals, photography, exploring, hunting? or is it just to play follow the leader? If you are trying to capture a particular image or scene with a video or camera, your attention is necessarily focused on that subject for X amount of time. What if a diver spears a fish and so does his buddy? Do you think both people are available physically or mentally to provide assistance? Not happening. A buddy system can and does work for a lot of people, but not for everyone all the time.
I don't spearfish or do photography. If I did, I would only do it with buddies I know I can trust and that are part of a team with shared goals. Outside of that, it gets very close to solo diving, as I see it.
Really for recreational diving? I think not. The planing is for one critical failure NOT two. You have a critical failure, you go to your pony and the buddy is on his own to make the ascent. If he runs out of gas or has a simultaneous, instantaneous critical failure (and he does not have redundancy himself), then you buddy breathe or die.
We don't plan for everything.
In case my wording was unclear, I agree you normally only plan for 1 critical failure. My point was that I think proper gas planning should account for 1 diver to have a complete loss of gas - so my reserve should be enough to share gas with my buddy in case he has a catastrophic failure. I don't also plan for what to do if I also have a catastrophic failure - that is one step too far, I think.
, sure why not? If it makes you feel better and safer go for it. They are way more reliable than a buddy, they are always there.
