GUE and Sidemount position ?

[decompression]

When it comes down to it, I think it's hard to beat the combination of solid knowledge of Deco theory, a Quality PDC and a back up (cut profile/RD).

 

[elmo]

I came here expecting a discussion on how sidemount could fit into GUE's system.
But thanks for letting me read several pages on UTD's Ratio Deco

 

[Dan_P]

You continuously bring up the subject of things being comparable for mixed teams and scaling. I dive with my GF's set the same whether I'm diving a 20ft warm water reef, a 100+ft cave, or diving under the ice. I do it with mixed teams on ccr with no issues either. WHY is RD better than using a computer to essentially eliminate the risk of human error?

I'll bring out an example.

MT Haven, Genova.
My buddy (MX-Z/Z) and I (Z) cruise up north from Porto Ercole, deciding to dive this big huge mother of a wreck on the way. We have some 21/35 and 50 with us in the boot from the week's run further down south. We know we're bound by gas density/END to around 51m and avg. ppO2(1,2) to just shy of 48m.

On the way out, the captain tells us more about the wreck. We're set perfectly for the intersection between the deck and the superstructure.
So, we can make our way down there, check it out, and then make our way up the superstructure and see what we see towards the top before we hang loose by the line to complete our deco.

Literally 5 seconds of RD gymnastics in the boat tells me I have a bottom time at that depth of 24 minutes. That's taking into account deco, gas logistics, what we have with us, what we each can and cannot do, and contingencies.
15 more seconds spent bonding with buddy, we're on the same page. Now we both know exactly what the deco plan looks like. Job done.

If we want to hang higher than 48m, we adjust as we go. No biggie.

The captain overheard it all. Now, the captain was a cool cat, funny dude too. Dove that wreck as much as anyone, probably. Don't get me wrong, he had looked at me funny when he saw just a 330 and a compass on me, and had mentioned it, but it was all in good spirit. We made a few jokes about deco on the fly earlier on - good vibes and that. He tells me we have 60 minutes max.
Carrying on the good spirit of the chat, I tell him "it's cool, we only need 58".
He's pissing himself, thinking I'm joking.

58 minutes after splashing in, he starts asking questions. Questions a computer couldn't answer on the fly.

In between, some 4 minutes in, I'm looking at this hold in the deck, in front of the superstructure. To have a peek inside, I have to drop a bit. So, do I stick my head down to 51m like a rascal, breaking the max. of 48m I set out for?

A computer would either say "*beep*, *beep* no, *beep, dangit* it's against the law! Or I'll change your *beep-ing* schedule on you!", or "sure dude, hang loose, we'll see what we see when you decide how long you want to hang out there, like. Gas, schmas".

My call?
Yep, that would work for a quick peek because I can depth average just fine and I know my average depth would still be well under 48m even if I stay at 48m after and that's within the average of ppO2 1,2, which is what I want for my strategy to hold true and being on par with a breather, while within END=30m, and I have gas to complete my hangs for this, even if my buddy runs dry or someone else shows up all messed up. Heck, I could even squeeze an extra 5 minutes of bottom time out of it if I want to, it being a square dive and all, if my gas tracks it.
My buddy knows it, too. That's all in the blink of an eye. Gas, deco, mixed team, rock bottom, accounted for.

A computer wouldn't help me make the call. I would need to be tapped in to make it. Can you do that with a computer? Of course, but would the help in figuring out depth averaging really be that much of a help - and would a bunch of divers probably go the easy way and just "blindly follow" the computer instead, losing track of the important stuff in the process - maybe putting them in actual harm's way?
Heck, a bottom timer does depth averaging, if that's all I'm looking for in a computer.

However, I'd like to circle back to the statement that Ratio Deco is dangerous. I say it's unsubstantiated. You say there is plenty evidence to support that it's dangerous;

You've pointed to NEDU, which has nothing to do with the dives we do as it wildly overshot NDL, on a deep air dive at that, and then included deep stops on air.
That says, at best, deep stops was or is overemphasised to some degree. That's not what I'm arguing here - what I'm arguing, and what it doesn't say, is that that RD is dangerous.

You've pointed to the Italy project, saying that it concluded RD is dangerous. I've all but quoted it word for word in saying the following, based on the conclusion section of the report:

1) There were no higher incidence of DCS in the dives carried out with RD.
2) There was no statistically significant difference in bubble presence in the dives carried out with RD.
3) There was a difference in inflammation levels, but we don't understand the significance of that.

That's comparing RD to a gf model that has a higher than most emphasis on the deeper portion of the dive, 30/80.

So, again, please refer to this scientific evidence that RD is, as you say, dangerous?

I can't think of a single reason why I'd want to stop using a computer. It's easier, it eliminates human error. It allows people to help me if I do make a mistake. And it looks cool.

If you have a computer that looks cool, okay, fair game. There's no touching cool. I do have a sweet eye for the Freedom, to be honest. The bottom timer version, though.

 

[tbone1004]

I have said that it is less safe, not dangerous. Don't put words in my mouth. You have yet to prove that it is more safe than running a computer or table with known and proven algorithms. Is RD more convenient to rough cut decompression, yes of course. Deco planners on computers are annoying as hell and you can't "plan" on a computer while in the water, but that doesn't mean it is safer. You have a "strategy" that is your rough plan from the surface and know that your computer is going to run the exact calculations to make sure you don't botch something if things change.

We have literally everyone in the scuba diving community advocating for computers with known algorithms except for a single individual and those that follow him. It is up to you to prove to us that your position is safer than ours. AG is not able to do that himself, I highly doubt that you can

 

[Dan_P]

@tbone1004 okay, less safe then. I hear you.
What we know is less safe, is DCS and bubbles. Nothing to report.
Inflammation - we don't know the significance.
That's the word.

I'm eagerly awaiting more, as I'm sure we both are.

But:
What I'm saying is not that Ratio Deco is safe and computers aren't. Both appear to be safe.
I'm saying that I, as you, find RD more convenient. I'm saying it includes many highly relevant factors, which adds value that an algorithm - optimal or not - on it's own, couldn't possibly.
I'm not saying that a human brain can't include those factors separately from a deco table and add it all up, tailoring a strategy for each dive.
I'm saying that RD helps me do it quickly, on the fly, in or out of the water, for any dive.

As for myself proving that it is safer, that's for the "your way is wrong and my way is right"-discussion. I feel that's a different one from ours.

 

[Doby45]

THIS HAS NOTHING TO DO WITH SIDEMOUNT AND GUE. We need one more damn deco argument thread like we need a hole in the head.

 

[MichaelMc]

Agree, I think some of you are mods, can you split this off to a deco thread. I'm more interested in sidemount, the title, than deco versions right now. This is a seriously long digression.

 

[Dave Bevan]

So getting back to the subject:-

Quest 17.2 has an article

Modern Sidemount Diving: The Benefits of Starting Early
by U. Welcker

Quest 17.1 has

Choosing a Sidemount Rig
by R. Neto

Quest 15.2 has

GUE’s Core Values: A Question of Identity
P. Alexakos, Ph.D.

It would be best to read these articles and get the information 'from the horse's mouth'. However, they are not freely available to the public so I don't want to post them here. It may be possible to borrow a copy from somebody who is a member so you can have a look.

What I can say that if the agency was against sidemount they certainly wouldn't put so much emphasis on it in the article. Whether or not they'll introduce a training package for it. I'm not sure.

 

[Kevrumbo]

Objectively again, the point is as a means to retain the DIR Long Hose Paradigm, the UTD Z-system is currently the only way to mechanically achieve this in sidemount. It remains to be seen if GUE chooses to develop this late in the game, a better more elegant gas distribution to reg solution to go along with the Halcyon Contour sidemount harness . . .

. . ..

GUE teaches a sidemount class that's highly specialized and not regularly scheduled in their general course offerings. The prerequisite is Cave 2 and a "need to know" request for learning the techniques of passing through overhead restrictions within the DIR paradigm. Otherwise as a business, training & product model, and in contrast to UTD, they see no reason to currently market a sidemount course or advertise any additional equipment besides the Halcyon Contour sidemount harness for general recreational open water scuba.

For doubles sidemount, they utilize Lola cylinder valves with a flexible crossbar interconnection routing in front of the diver at chest level between the two cylinders.

 

[decompression]

Love to see pictures of that......