MichaelMc
Working toward Cenotes
I think there not too many of you disagree that solo divers will need some sort of redundant supply, so, maybe its a good idea to stop discussing that to keep the focus. In this discussion, technical divers are over-represented, how can we conclude anything reasonable for rec divers if you do not take off your tech diver or solo diver hat?
I'm happy to not focus on solo or tech dives. Though not happy to forget skills and ways or mitigating risks learned there.
So let's look at some rec. dives:
With an adolescent or younger buddy: A decent pony lets me handle any gas emergency without stressing them or relying on their reaction under that pressure. Necessary? No. I could put them through all that, and likely get gas from them if needed, without them doing any kind of good job in the process. But a pony would be a much better plan. Instead of "make sure you save your uncle on the dive today".
With divers I know and trust as very solid: No not necessary. Though it adds an extra layer of ease when we're both redundant.
With unknown divers: Mmm. Well, which of the above two cases are they closer too? Can I know that before getting on the boat or in the water with them? Will I even know after a dive when things seemed to all go well, as they seem fine but are actually totally useless if something happens? A pony is not required... as I could still likely get air from them even if they are useless, but it would give me more peace of mind that I'm not rolling the dice on their reactions.
Having a decent pony simplifies my pre-dive pairing up process and the dive itself to "am I comfortable helping you at need" instead of "am I comfortable relying on you at need for gas right now". A modest cylinder at my side is a small price to pay for that simplification and reduced worry before and during the dive.
I think a better question is:If every single rec diver in the world carried a pony/stage, would that affect fatality or general safety stats and in what way? Think of every rec diving boat you have been on, and try to imagine if everyone used a pony..
@Lorenzoid asked a good question. What are the thresholds/borders for recommending a pony; vis, depth, temp?
If every rec diver was a much better diver, would that affect fatality or general safety stats and in what way?
Everyone being much better divers would clearly make a difference. Yet I can't make all divers better. I can hedge my risk when I'm not sure how good the diver I'm with is, and I can handle the minimal pony complexity as I am a better diver.