Slow tissue on gas from stops

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E.g. If I need to bring two divers from 50m to 6m from the end of the bottom portion because that's where my next gas is (oxygen) as I've planned to do that based on an (extremely shallow) "optimal" algorithm, it's a logistical issue.
I'd prefer nitrox 50, which I can deploy at 21m. Example of less bottom gas requirement.

E.g. If my buddy and I are diving, I'm on O/C and he on CCR, our gasses and asend profiles become identical, even if he bails out (maintaing a pp02=1.2 average on O/C). Example of system interoperability.

E.g. If I'm on deck and dive site A is out, I can skim our gear and gas, and have a new dive plan ready within 10 seconds. Example of ease of planning.

E.g. If I'm on the deepest part of a wreck and find life sucks there, I can adjust my plan and know exactly what I can do with the gas available to me if I hop up to the shallower portion, before I do so. Example of ease of adjustment.

E.g. If I'm teaching a team and I want to develop or control their level of awareness, I can see if/how they adjust their deco time based on various stimuli. Example of value as a training tool.

None of those examples require a deep stops approach. Not one.
 
Allow me to illustrate ... [chart]...[chart]...[chart]...[chart]...[chart] ... to the point we were discussing in terms of "unsafe" versus "suboptimal"

That was a lot of charts to basically say you agree bubble models produce profiles that are "less safe", "suboptimal", or "not efficient" when compared to shallow stop models.

It seems "unsafe", to you, implies some degree of certainty of harm, and don't like its use as a comparative term (e.g. unsafe compared to ...). Since you have that pet peeve, I'd just suggest that when someone says, "Deep stops are unsafe", you simply say, "I agree. Bubble models, or RD, produce profiles with deep stops that are not as safe as other shallower stop profiles available to tech divers."
 
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The discussion is very interesting but going way over my head. I just do as my computer tells me and don't question it, however if would be interesting to learn a bit of the science. Are there any online resources that explain all this starting from the very basics?
 
None of those examples require a deep stops approach. Not one.

Which solution do you use that sorts it out?

That was a lot of charts to basically say you agree bubble models produce profiles that are "less safe", "suboptimal", or "not efficient" when compared to shallow stop models.

It seems "unsafe", to you, implies some degree of certainty of harm, and don't like its use as a comparative term (e.g. unsafe compared to ...). Since you have that pet peeve, I'd just suggest that when someone says, "Deep stops are unsafe", you simply say, "I agree. Bubble models, or RD, produce profiles with deep stops that are not as safe as other shallower stop profiles available to tech divers."

Actually, it's a lot of charts to show how fact and figure can easily be misrepresentative of truth.

And I think it seems that you're not open to the possibility that when or if you call something "unsafe" some might think that implies "some degree of certainty of harm" (or, the actual meaning of the word).

I feel that's a gross misrepresentation, and I think it's well beyond semantics.
And I don't think you have any basis for calling, heck, pretty much any level of gas mechanics emphasis, "unsafe".
And I think it illustrates very well an example of what I'm saying in regards miscommunication/misperception in the debate.

If you call a Ford "unsafe" because it has a 100.1m breaking distance compared to a Formula-1 racer's 100.0m, you're misrepresenting a fact.
 
@Dan_P : I have problems understanding what you're trying to say. You're a UTD instructor, so I assume that you have a fairly close relationship to "UTD ratio deco", which - to me - seems to suffer from the same reliance on deep stops and shorter shallow times as VPM (of any flavor) or RGBM do. Does the fact that UTD - AFAIK - teaches a deco method even poorer funded in hard experimental science than VPM or RGBM have anything to do with your arguments?

What are you really trying to say? That you're sore that non-scientists simplify and maybe over-interpret the recent clinical results, putting bubble model based algorithms in an even worse light than the careful and measured statements from the scientific community do? That you don't have hard arguments, but still want to defend a bubble model based deep stop algorithm? I can't find any clear message in your posts, except that you don't seem to agree with what the recent studies have shown.

Please explain. Because to me, your arguments remind me quite a bit of the tactics so brilliantly described in Conway's and Oreskes' "Merchants of Doubt"
 
The discussion is very interesting but going way over my head. I just do as my computer tells me and don't question it, however if would be interesting to learn a bit of the science. Are there any online resources that explain all this starting from the very basics?

I think "Deco For Divers", "Technical Diving from the Bottom Up" and "The Tao of Survival Underwater" are good books all.
"Basic Decompression Theory and Application" is a good one, too, but it's a heavier read.
 
@Dan_P : I have problems understanding what you're trying to say. You're a UTD instructor, so I assume that you have a fairly close relationship to "UTD ratio deco", which - to me - seems to suffer from the same reliance on deep stops and shorter shallow times as VPM (of any flavor) or RGBM do. Does the fact that UTD - AFAIK - teaches a deco method even poorer funded in hard experimental science than VPM or RGBM have anything to do with your arguments?

What are you really trying to say? That you're sore that non-scientists simplify and maybe over-interpret the recent clinical results, putting bubble model based algorithms in an even worse light than the careful and measured statements from the scientific community do? That you don't have hard arguments, but still want to defend a bubble model based deep stop algorithm? I can't find any clear message in your posts, except that you don't seem to agree with what the recent studies have shown.

Please explain. Because to me, your arguments remind me quite a bit of the tactics so brilliantly described in Conway's and Oreskes' "Merchants of Doubt"

No, I've illustrated well my point.
Misrepresentation or misperception of fact in the debate was the point, and it was illustrated a couple of posts back.

I've shown that I don't depend on a certain deep stop level, and besides, UTD doesn't even require the use of Ratio Deco in technical classes, so what's your point?
 
Again;

Misrepresentation or misperception of fact in the debate was the point, and it was illustrated a couple of posts back.

Obviously not well enough for me to realize what your point is. Which should be a little worrying for an instructor, IMNSHO

...Because to me, your arguments remind me quite a bit of the tactics so brilliantly described in Conway's and Oreskes' "Merchants of Doubt"

If you're genuinely in doubt as to my point, it's that there is an element of misperception in the debate. Findings and reservations are not being discussed in a balanced fashion - that is, even the discussions prompted within the reports we reference, are dismissed.

But you seem to be under the misguided impression that I must have an economic motivation, for reasons that I've shown you to be wrong.
Frankly, it looks like you're just trying to take a cheap shot.

So again, what are you trying to get at?
 
So again, what are you trying to get at?
I've told you that twice already. If you choose to believe that I have a hidden agenda, that's your problem, not mine.
 

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