Dish
Are you for Scuba?
Nice post, Ray.
NEDU Study
- Thread starter klausi
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No. That is the misrepresentations and invalid explanations that has been made all along... association by words only - the word "deep" and the word "bubble". Pretending the nedu test was equal or could be applied to tech diving. And then the distortions to VPM-B plans to force it into some invalid comparison with the nedu test. And by making up comparison methods that are invalid...
Kevin, it's your home made and invalid measuring / comparison methods and graphs at the center of this problem. These have been used to widely promote a fallacy position.
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Anyone could have done exactly the same trick with ZHL-C + GF 50/50.... make it look just like the failed nedu A2.... fiddle the graphs in the same way.... But that would have been an invalid representation of a model and comparison too - exactly what has been done to VPM-B.
There is no science to connect nedu test to VPM-B ... only opinions, and theories of some people. I have shown those opinion based positions to be invalid. post #116
These rebuttals I make, and valid supporting data I present, gets denied and dismissed, because it interferes with the agenda for change being promoted here. i.e. it's a battle of reputations vs real science facts.
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The nedu test... again...
The nedu test has no actual deep stops - only elongated shallow ones. The nedu A2 "bubble" model profile is a unique shallow (DGBM) design.... it is not like VPM-B or RGBM. The failed A2 BVM(3) has its own ideas of gas kinetics, quite different from other models.
ZHL-C and VPM-B, both produce plans that imply or create the same direction of risk, or orientation of extra deco time, as the successful A1 profile. i.e. adding more deeper time, automatically produces more shallow time. Only some RD or DIR theory tends to align a little with the opposite A2 concepts.
No one wants to point the finger (or mention) the real problem area - the RD and some DIR classroom theory and explanations. That's where the plans are hevily modified deep and cutting the shallow time can occur. Instead they use VPM-B as a proxy and blame it for other peoples problems.
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The nedu test explanation justifies it finding based on the standard gas kinetics. The successful A1 profile followed typical gas kinetics rules, and those same basic rules are used in ZHL-C and VPM-B models (and every dive computer too). The failed A2 supersaturation pattern and profile, followed its own unique model concept rules. There is no connection from A2 to real tech dive profiles or VPM-B.
The nedu test was designed to test the BVM(3) model, and nothing else....
The nedu test predictions and result, showed models that followed the basic gas kinetic rules, turned out to be correct. i.e. ZHL and VPM-B.
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Hi Ray,
Yes I can see your points.
Sadly, I do not have the wonderful public presentation style that Simon posses, or his excellent debating technique skills. Nor do I don't have the marketing experience that Kevin Watts (UWSojourner) has. We don't employ a PR person. It's just a hard nosed developer here, sorting out the noise from the truth and including it into the best deco planning tools available.
I can understand why people pick Simon's side first, based on his credentials. But the facts do not support these attacks on VPM-B. These people are looking for excuses and justifications for adding extra layers of safety through longer slower deco. However, they should not be using invalid measures and misrepresentation of VPM-B, just to create those points. They could easily sell their message on extra safety benefits alone, without stomping all over the existing work.
.
sealark
Contributor
I didn't take time to read all the posts I'm 73 over 9000 logged dives followed the Navy rules closely. Minor bends twice. long term effects are a result of diving. I have plenty Knees , Back, Hips shoulders, Neck Here is an interesting article for divers I assume was done by NEDU for rating military Divers for VA disability.
What would really make me happy is for you, Ross Hemingway, to apologize to the various scientists including Dr Simon Mitchell, Dr David Doolette, Kevin Watt and Neal Pollock for the years of professional slander, misrepresentation and obfuscation of their work. This apology should be made on all the diving websites you have commented on since the NEDU study, including Scubaboard, RebreatherWorld, the Deco Stop and Yorkshire Divers. It could perhaps repair your tattered reputation also.
It would also make me happy if you apologized to divers who have been subjected to your misleading diatribes and who have been bent over the years following V-planner. Andrew Ainslie springs to mind.
Finally it would make me happy if you would adopt best practices for decompression theory in your communications and website, which at present include the concept that if one wants to use VPM-B pad for shallow stops.
It this way you could become an actual proponent of safer diving practices.
*edit
For clarity I do not know any of the above named individuals personally, nor have I met them or attended any of their presentations or workshops. The only way I know them is through reading their online postings.
It would also make me happy if you apologized to divers who have been subjected to your misleading diatribes and who have been bent over the years following V-planner. Andrew Ainslie springs to mind.
Finally it would make me happy if you would adopt best practices for decompression theory in your communications and website, which at present include the concept that if one wants to use VPM-B pad for shallow stops.
It this way you could become an actual proponent of safer diving practices.
*edit
For clarity I do not know any of the above named individuals personally, nor have I met them or attended any of their presentations or workshops. The only way I know them is through reading their online postings.
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Hi,
I have met all those people except one...
Andrew Ainslie used to be our CCR X1 and X-Link tester... He and I talked often about his diving and feedback on VPM-B and the programs. He never once mentioned a single problem to me or anyone... And then one day, a year after he shifted to a different computer brand... he suddenly remembered 13 incidents..... I don't believe it, and neither should you. But we have all his dive logs, so I asked him to point out which ones gave trouble, so we can all take a look.... still waiting.
Simon is a nice guy in person, and puts on a lovely presentation.... I can't talk about Simon on this forum anymore, but I have expressed my thoughts elsewhere.
David is a true scientist, and defends his work and reports, like anyone should. I have shown many times how the implied bridge to tech, is simply not there. But this anti-deepstop argument goes way back, to the late 90's, and into the USN where they were first thinking about how to shift off the old USN56 tables.
I like everything Neal Pollock does... a real scientist, who keeps it all well balanced.
UWSojourner (Kevin Watts) and I have been arguing over GF for a decade.
As I have shown many times, I don't like his graphs or charts, because they are often use invalid methods, are biased, or are otherwise unsound.
I stick up for the facts and the truth,.. not going getting conned by invalid noise, trends, other peoples wishful thinking or agendas for change. From my vantage point, the bulk of divers are doing just fine as is.
It would be most inappropriate for me to dictate how people dive... I am not going to limit existing tools, just so some people here can feel less guilty about their over exaggerated choices. We provide all the tools, and divers can choose for themselves, or follow the advise they receive..
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Ross- You seem to feel that your work is being attacked and maligned. That makes sense to me but I think you are seeing things in a way that is not shared by others. Your response seems to be blinded by a strong case of confirmation bias and there is an almost paranoid feeling to your defense of something that you are personally invested in. To a casual observer it does not seem that anyone is out to get you or VPM-B but you have created a dynamic in the discussion where there is no room for open-minded exchange of ideas.
Most of the other participants in this discussion are on a quest for knowledge in a field dominated by uncertainty and hobbled by a shortage of real world testing due to it's inherent risk. These other participants have varying levels of confirmation bias but it appears that in many cases, their bias initially favors bubble models and deep stops because of the time frame or the nature of their training. Where others are open to new ways of looking at decompression modeling, you are invested in a set point of view and lacking a compelling argument backed by data, you have attacked the other participants. It is not a smooth delivery or presentation that you lack. It is an inability to see the consequences of your actions and a lack of social discipline that is hurting your message.
It is a pity because you could offer so much to the discussion if you didn't appear to be paranoid and vicious. Please don't think that the difference between Simon's success and your failure is due to his smooth delivery. If anything, his advantage is that he respects others and is able to listen to those with different ideas with an open mind. Those are attractive characteristics in anyone but especially in those that seek the truth.
A ScubaBoard Staff Message...
All posts referring to deliberate lying have been redacted, even some that may have been just within TOS. As explained before, there will be NO repeat of the mud slinging that derailed every other thread on this subject. Any complaints feel free to report this post and the other mods will look at the situation.
UWSojourner
Contributor
From Dr. Neal Pollock:
#305
"Unfortunately, Ross, I do not believe that our core positions are in agreement. The differences are much greater than simply semantic."
#356
"Bubbles are a clear indicator of decompression stress. Getting off the bottom (that is, skipping the deep stops) can reduce tissue loading in intermediate and slow tissues. No matter what is done at depth, prolonging shallow stop time is effective at reducing VGE in individuals predisposed to develop them. Other strategies might work, but I am most impressed by those based on credible evidence. I call prolonged shallow stops really cheap insurance."
#375
"The impact of deep stops is not that they target some different physical reality. It is actually quite simple; the extra time spent deep allows more inert gas uptake in the relatively undersaturated intermediate and slow tissues. This is simply a loading problem that subsequently produces a higher degree of decompression stress. If there is less uptake at depth, ascent to a relatively shallow stop has much less risk. The idea that deep stops controlled bubble growth is one of the armchair arguments that has not lived up to human testing ... As with all the protocols we developed and subsequently saw fail, it is time to respect the data over the hand-waving."
Very well balanced.
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