Time to adapt to necessary tools.

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And if sidemount isn't needed to do a dive than you shouldn't be using it.
If someone want's to do their quarry dives/tourist cave dives or whatever in SM why shouldn't he or she? For most dives it doesn't make much of a difference whether you're in BM or in SM IMHO.

Then there's another issue of getting yourself into a place where you can't be a good buddy, which is certainly the case in some small caves and gnarly wrecks.
That is an issue, I agree. It's the only issue though and it's doesn't apply in OW.

...but when folks strap on a tool for a dive that doesn't need it, such as OW sidemount...
You could also say that BM is a tool that they don't need.

I've seen tons of divers in DIR style rigs doing ow dives, they don't need the 7' hose, they don't need that can light and in many cases don't even need the twin set. People use that stuff because they like to dive it, people think it's a cool... same can be said for SM and CCR divers.

Let's face it, the vast majority of dive being done around the world are not hardcore cave dives... how many of the Halcyon wings that have been sold around the world have ever seen a cave and how many of those have seen more than the first 1000' of Devils or JB?
I really don't understand why you guys have an issue with SM diving.
 
.... when folks strap on a tool for a dive that doesn't need it, such as OW sidemount and shallow rebreather.

Two issues:

1. We improve our skills and familiarity by spending time in a given equipment configuration. Conducting OW recreational dives in 'technical' kit, such as sidemount, manifold doubles or CCR, is a method of skill and experience improvement. The alternative would be to preserve using that equipment ONLY when it's capabilities are needed - thus we gain experience on the kit only when the repercussions of weak familiarity can hurt us. That's a flawed outlook.

2. Technical agencies, including GUE, demonstrate a philosophy of using equipment 'inappropriate' to a given dive - as it conforms to global standardizations. Examples would be:

a. Using drysuits in the tropics.
b. Backmount, isolated doubles on shallow, no-stop dives.
c. Equipping with $1500 canister torches for shallow, tropic reef dives in exemplary viz and light conditions.
d. Long hose use in open water, no-stop, dives.

.... the list goes on.

It's flawed to apply a "inappropriate kit for the type of diving" argument to sidemount, when the same argument is never applied to backmount technical configurations.

There's no reason not to dive sidemount in open water conditions. The provision of gas redundancy is justification enough. Beyond that, the diver gets the best familiarity with equipment that they may use in dives that demand sidemount/redundancy etc.

If an agency restricts sidemount (or CCR) to ONLY dives that demand it.... then it will only create a cadre of divers who are under-familiar with equipment that they intend to use on their most challenging and advanced dives.... sounds stupid to me.
 
Two issues:

1. We improve our skills and familiarity by spending time in a given equipment configuration. Conducting OW recreational dives in 'technical' kit, such as sidemount, manifold doubles or CCR, is a method of skill and experience improvement. The alternative would be to preserve using that equipment ONLY when it's capabilities are needed - thus we gain experience on the kit only when the repercussions of weak familiarity can hurt us. That's a flawed outlook.

2. Technical agencies, including GUE, demonstrate a philosophy of using equipment 'inappropriate' to a given dive - as it conforms to global standardizations. Examples would be:

a. Using drysuits in the tropics.
b. Backmount, isolated doubles on shallow, no-stop dives.
c. Equipping with $1500 canister torches for shallow, tropic reef dives in exemplary viz and light conditions.
d. Long hose use in open water, no-stop, dives.

.... the list goes on.

It's flawed to apply a "inappropriate kit for the type of diving" argument to sidemount, when the same argument is never applied to backmount technical configurations.

There's no reason not to dive sidemount in open water conditions. The provision of gas redundancy is justification enough. Beyond that, the diver gets the best familiarity with equipment that they may use in dives that demand sidemount/redundancy etc.

If an agency restricts sidemount (or CCR) to ONLY dives that demand it.... then it will only create a cadre of divers who are under-familiar with equipment that they intend to use on their most challenging and advanced dives.... sounds stupid to me.

I think I generally agree with you. Training with gear is one thing. I think that's fine and a smart thing to do. Using it just to use it...not so much...

I'm not a fan of dress up make-pretend technical diver. You'll rarely find me with doubles on a shallow reef dive (maybe if I have to borrow tanks), and I often leave the can light at home unless vis is poor. That said, doubles don't really add much (if any) risk to a shallow reef dive, while a CCR certainly does.
 
Imo the issue isn't so much using the right tool for the job, but when folks strap on a tool for a dive that doesn't need it, such as OW sidemount and shallow rebreather. Then there's another issue of getting yourself into a place where you can't be a good buddy, which is certainly the case in some small caves and gnarly wrecks.
Let's talk about that for a minute.

Some people prefer side mount because it's more comfortable, allows more range of motion, and allows more flexibility in tanks that can be used. A side mount diver can also show up pretty much anywhere on the planet that has a dive operation, rent a pair of AL 80s and be ready to dive in about 5 minutes.

If you're diving to deeper, but still recreational depths, a pair of side mounted AL80s allows complete redundancy plus a greater reserve than diving a single AL 80 on each dive. If you dive half the gas on dive one, and half on dive two you've got a massive reserve on dive one, and you've also got a larger reserve in dive two as you are leaving none of the gas on the boat.

We've dove side mount for about 5 years now - half our cave diving career, and I've noted that we can go a lot more places in caves, including places we could not go back mount without significant contact with and damage to the cave, and do it cleaner and with less effort. With a 5 ft hose on each tank, I've also never noted any decrease in our ability to support each other on the dive, including gas sharing through some pretty tight restrictions. However, that's arguably overkill as the odds of ever losing all your gas are virtually zero, and with proper gas management, you'll always have adequate gas to exit in either tank to exit the cave, so reserve gas your team mate is just gravy on the potatoes.

If I dive a single tank, with a usually with a BP and wing, and then it's because I want to use a (modernized) double hose regulator. That might seem pointless to some, but on a pretty fish dive it produces much more diffuse bubbles that are also behind my head. I've actually had fish come up and "hide" in front of the safety of my mask or camera and observe the bubbles coming from behind my head. Back in the day when I dove a Dolphin, it served a similar function - the SCR rebreather produced comparatively few bubbles spaced at wide intervals, and that use of a rebreather still makes sense today.

Rebreathers are not always about going to 300 plus feet. Consider a long dive in a shallow cave in the 60-90 ft range. In a large system, that's still deep enough to require a stage or two to get you where you want to go and back, and once you're in the two-three stage range, if you can't use a scooter, you're at a point where you're now burning extra gas to carry extra gas. It's not unlike an A-4 with three 300 gallon drop tanks - you almost never did that because the extra weight of the extra fuel in a 3rd drop tank created so much induced and parasitic drag that it required burning the extra fuel just to carry the extra fuel, with no positive impact on ferry range.

In the case of a "shallow" rebreather dive like the one above, having each team member drop one or two stages at key points for team bailout allows you significantly more time and more penetration for a lot less effort. If you're doing several dives in the system, you can leave them at those key points and further decrease the workload on subsequent dives, and/or increase the available bailout gas without having to do set up dives.

Are there trade offs? Absolutely. But if you're honest about it, you'll acknowledge that there are tradeoffs in back mount as well.

Believing that OC back mount should be the default technical dive configuration is totally dependent on one particular set of starting assumptions, biases and priorities.
 
If I show up somewhere that doesn't have doubles, I'm fairly certain that they also don't have helium. You know how I feel about deep dives sans helium. Shallower than 100ft I'm of the opinion that a single tank is adequate. Doubles (in some form or another) might be nice in the 80-100ft range, but certainly not required for the dive to be safe.

I've wrote about this elsewhere, but a friend of mine had bad gas and had to share air through the exit. Air air everywhere and not a psi to breath! The option really needs to be there, imo. I think most SM folks are well prepared in this regard. All in all while there are some real disadvantages, I don't think SM is the worst thing in the world.

In contrast, I do think that the overuse of rebreathers isn't smart (and maybe the worst thing in the universe). What you describe in your longer range shallow cave is probably a reasonable example of where a RB could provide real benefit, but also a rare situation. Where are you doin' 3 stage dives without a scooter? Now, for a swim down the peanut tunnel, not so much. I think RB use in that context needlessly adds additional risk to the dive. Same thing with look at fish dives. I get it for remote locations with high helium costs, long dives, deep dives, etc. But a swim to Olsen or a scooter to the heinkel? OC all day.
 
From my experience, a lot of CCR divers are putting hours on. It's needed, as many training courses have prerequisites in hours of diving on a given unit.

Backmount and sidemount doubles should do the same... IMHO.
 
/...Shallower than 100ft I'm of the opinion that a single tank is adequate. Doubles (in some form or another) might be nice in the 80-100ft range, but certainly not required for the dive to be safe.../
So you're ok with penetration of a wreck at 100' with a single tank. Good to know.

/... All in all while there are some real disadvantages, I don't think SM is the worst thing in the world.../
Proof that even PfcAJ can evolve - and evolution is the whole point of the discussion.

/...In contrast, I do think that the overuse of rebreathers isn't smart (and maybe the worst thing in the universe).../
Proof that PfcAJ still has a long way to go.

What you describe in your longer range shallow cave is probably a reasonable example of where a RB could provide real benefit, but also a rare situation. Where are you doin' 3 stage dives without a scooter? Now, for a swim down the peanut tunnel, not so much. I think RB use in that context needlessly adds additional risk to the dive. Same thing with look at fish dives. I get it for remote locations with high helium costs, long dives, deep dives, etc. But a swim to Olsen or a scooter to the heinkel? OC all day.
I used an extreme example - but so did you. Where exactly do you draw the line in the middle? That once again depends on your biases and your priorities.

Let's also talk about END. Let's say you want to decrease the END and let's say you want to do it affordably. Helium used to be comparatively cheap. It's not anymore and it's most likely not going to get any cheaper. At some point OC will force the choice between an END deeper than 100', a rebreather, not diving much, or not doing some dives at all. It'll be your choice.

----

Let's talk about the evolution that has occurred in the history of diving over the last 50-60 years.

In the 50s and 60s there were divers who opposed single hose regs. The double hose regs of the day breathed better and they were much more reliable in cold water and silty water. They still are for that matter as both the first and second stages are dry sealed. Single hose regulators were cheaper to produce, but they were regarded as just that - cheap entry level designs. They've evolved a lot since then, as have the attitudes regarding their use.

Similarly, many divers were opposed to using an SPG as they felt that the warnings provided with an unbalanced first stage and a J-valve combined with proper dive planning, a solid understanding of your gas use rate, depth and a dive watch were sufficient. SPGs could fail after all. And breed complacency in new divers. You encounter the same argument today regarding computers. Equipment has evolved, but as always attitudes often seem to lag behind.

In that regard, the first mutli-level computer was the steel 72 as most divers felt it was impossible to get bent on a single tank first dive of the day with the limited gas in a steel 72. It was arguably a lot safer than diving Scubapro's aptly nicknamed Bend-o-Matic, which was really a mechanical single compartment dive computer using pressure to force gas through a filter to move the needle. Dive computers have evolved a lot since then.

BCDs were also seen by many as an equipment solution for a skills deficiency. If you had a balanced rig and adequate skills, then conducting a dive without a BCD was not a problem. It was argued that adding a BCD was just adding more complexity and more things that could fail. At some point using one on a deep dive with wet suit compression and double tanks started to make sense, but I imagine those same divers would say it's not needed on a shallow water single tank pretty fish dive. Others would say, and some still say, that using double tanks allows a recreational diver too much gas as it allows a recreational diver to get into serious decompression problems.

Consequently a diver in the 1950s or 1960s with a single steel 72, no BCD, no SPG and a J-valve would be considered the acceptable norm for a shallow pretty fish reef dive. Take a pair of modern recreational divers today with single HP 100s, BCDs, SPGs, the simplest of dive computers and 32% nitrox, transport them back to 1960 and drop them in the water, and you'd find divers bitching about overkill, unreliable technology and lethal gas mixtures.

I started freediving in the late 1970s and got scuba certified in 1985. Even at that late date I still encountered "old" divers with many of those antiquated attitudes who had simply failed to evolve. What they did still worked well in their minds so they saw no need to change, and worked hard to point out the downsides. I dove through the era of voodoo gas when every training agency was opposed to any gas mix other than air.

If you talk to old cave divers from that era they'll talk about doing a couple hours of decompression on a dive where we might do 10-15 minutes today, as they had to do it on air and calculate the deco based on the max depth for the entire dive. Things have thankfully evolved.

Which is once again the point. There will no doubt be some evolutionary dead ends, but some of those new idea will take diving in some very beneficial directions, and some of those "old" ideas start to make sense again once the technology evolves.

For example, prior to the late 1950s, the rebreather was the preferred underwater breathing device for cave diving and from 1946 to the early 1960s use of rebreathers in caves was common and cave diving on OC was virtually unheard of until the mid 1950s. Rebreathers simply allowed more penetration than the OC equipment in the immediate post war period. What changed was improvements in OC technology relative to the limitations in the rebreather technology of the day. However, in the last 60 years rebreathers have evolved, and the balance has arguably changed once again. A modern rebreather is much more reliable and affordable than in the past, the technology is mature, it offers more time under water with less decompression, much more efficient use of gases and the ability to use helium on any dive deeper than 80ft, or even 60 ft if you choose.

You can wail against those advantages and point out all the ways a rebreather can kill you, but in 20 or 30 years someone will be talking about how it was in the old days, when guys like this ancient dude PfcAJ used to talk about how overuse of rebreathers isn't smart and was maybe the worst thing in the universe.

If I'm still around, I'll be laughing.
 
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