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--Boundary_(ID_CS6AibwRPT3BIxLSG4IuLg) Content-type: text/plain; charset=us-ascii Content-transfer-encoding: 7bit Hi John, Thank you for the insights, please read below. john.r.strohm@BI*.co* wrote: > >Do you, or the WKPP, have an algorithm that can > >actually demonstrate the clear advantage of 50/100 decompression? I'll bet > >that the answer is: "No". Why do I know that for a fact? Because if you did > >have such an animal, there is little doubt in my mind that you would take > >great pleasure in putting my nose in it. > > Guy, you are probably correct when you say that the WKPP doesn't have such > an algorithm. > > On the other hand, the question you asked is a strawman. The real question > is whether practical experience shows that 50/100 deco is better. The real > answer, developed over many thousands of diver-hours in the Woodville Karst > Plain, is "Yes, beyond any reasonable doubt." They haven't comparables experience with the 36/80 to make a claim either way. They've always done it with 50/100 because the logistics of that combination is the only one that can be used with any practicality for the scale of the project they are undertaking. That is just a logistical fact. Here's another one for you: I bet that WKPP doesn't have a quarter of the experience with 36/80 as with 50/100, on second thought, make that one tenth. In fact I would stake that the WKPP doesn't have 1/100, that's one percent of the experience they have with 50/100 in using 36/80. I'll go further to say that it's probably impossible for them to garner that level of experience with the 36/80 combination, they'll be wiped out, there are just not enough person-hours in a year to do that. Remember that it isn't just the effort in blending, but it's also tweaking all those schedules to make sure everyone is both offgassing enough, and not toxing out. That would be a very dirty job, and I certainly wouldn't wish it on anyone. And that you see, is my point. > > > Physics and medicine are both empirical sciences. Theory is well and good, > but practical experience trumps theory every time. A theory that does not > agree with the practical experience is at best incomplete, more likely > wrong, possibly very dangerously wrong. Decompression develops out of both > physics and medicine, and, as such, must equally be regarded as empirical > at the core. This means that you cannot ignore practical experience in > discussion of decompression theories. Your hypothesis, that 36/80 deco is > just as good as 50/100, flies directly in the face of the WKPP experiential > database, and must, by the fundamental rules of empirical science, be > discarded or modified. There empirical database could only hope to validate 50/100 decompression, and in now way allows comparison with 36/80 statistics that do not exist in their database. It would also fly in the face of common sense to condemn another approach to decompression on the absence of similar test data. Yes they could provide guidelines, and statistics on using 50/100 deco with a certain confidence level, no question. It does stop there. They do not have the empirical data to compare with other options or decompression schedules unless they undergo comparable field studies. Again, that seems to be acceptable from an auditor's point of view. A final point on the debate regarding theory and empirical models. We know for a fact that all applied sciences strive to perfect models that apply to the real world with a certain level of confidence, and with a certain level of computational efficiency. It is rarely the other way around. The human race used to take centuries to build monuments, and the effort was often one of trial and error. Today, we errect structures that are true modern day monuments, and we do this in a matter of weeks. Likewise, we have a rather high level of expectation on the durability and reliability of those structures. Would it be acceptable to you to hear every evening, on the six o'clock news that another skyscraper just collapsed? Is this crystal clear? Can we all make the leap here? We cannot wait for a person- century of experience to cut a decompression schedule. We must have models that will, within reasonable bounds of confidence, take us to and from where we want to go, and we must do this between the time it takes to blend, and the time it takes to get ourselves to the site. Are we all on the same page? At the end of the day, to every diver on the face of the planet, it is the model that will be of prime import. Dependence on a single decompression strategy negates flexibility, and could prevent someone from diving given (other) logistical constraints. Flexibility is again paramount. > > > NOW, if you had instead advanced the statement that "Existing theory says > that 36/80 deco should be just as good as 50/100, maybe a little better, > but practical experience shows in detail that this is not so, and therefore > we need to refine the theory", then this particular flamethrower party > would not be happening. That's a roger John. I must say that the needle that broke the camel's back was indeed the statement that 50/100 was better, and if you just look at the residual tissue numbers... Human nature, after that statement, well, I thought that if things were getting this silly, it was high time we aired all the dirty laundry. It could have been less messy, but this is hopefully stimulating, and will prevent folks from going in with blinders on. Some of the "myths" were a hazard, and it is important for people to realize the implications of what they are saying. Details do count in this business. We collectively accept the algorithm calculating as if it was 100% O2 all the way, but do we stop and think that we're not doing that? Tell me that doesn't matter. We collectively think that taking breaks from pure O2 decompression increases lung efficiency, that's wrong. Taking breaks curbs lung damage, possibly prevents it, and mitigates decreased lung efficiency. Why do people have this false assumption that lung performance is somehow enhanced by taking breaks from pure O2 breathing. This is just another dangerous myth. Yet we accept these things, and we even berate people for pointing these realities out. Double expresso here, coffee just isn't cutting it! This will be of service, maybe a bitter pill, but that's life. -- Guy --Boundary_(ID_CS6AibwRPT3BIxLSG4IuLg) Content-type: text/html; charset=us-ascii Content-transfer-encoding: 7bit <!doctype html public "-//w3c//dtd html 4.0 transitional//en"> <html> Hi John, <p>Thank you for the insights, please read below. <br> <p>john.r.strohm@BI*.co* wrote: <blockquote TYPE=CITE>>Do you, or the WKPP, have an algorithm that can <br>>actually demonstrate the clear advantage of 50/100 decompression? I'll bet <br>>that the answer is: "No". Why do I know that for a fact? Because if you did <br>>have such an animal, there is little doubt in my mind that you would take <br>>great pleasure in putting my nose in it. <p>Guy, you are probably correct when you say that the WKPP doesn't have such <br>an algorithm. <p>On the other hand, the question you asked is a strawman. The real question <br>is whether practical experience shows that 50/100 deco is better. The real <br>answer, developed over many thousands of diver-hours in the Woodville Karst <br>Plain, is "Yes, beyond any reasonable doubt."</blockquote> They haven't comparables experience with the 36/80 to make a claim either <br>way. They've always done it with 50/100 because the logistics of that <br>combination is the only one that can be used with any practicality for the <br>scale of the project they are undertaking. That is just a logistical fact. <p>Here's another one for you: I bet that WKPP doesn't have a quarter of <br>the experience with 36/80 as with 50/100, on second thought, make that one <br>tenth. In fact I would stake that the WKPP doesn't have 1/100, that's one <br>percent of the experience they have with 50/100 in using 36/80. <p>I'll go further to say that it's probably impossible for them to garner <br>that level of experience with the 36/80 combination, they'll be wiped <br>out, there are just not enough person-hours in a year to do that. Remember <br>that it isn't just the effort in blending, but it's also tweaking all those <br>schedules to make sure everyone is both offgassing enough, and <br>not toxing out. That would be a very dirty job, and I certainly wouldn't <br>wish it on anyone. <p>And that you see, is my point. <blockquote TYPE=CITE> <p>Physics and medicine are both empirical sciences. Theory is well and good, <br>but practical experience trumps theory every time. A theory that does not <br>agree with the practical experience is at best incomplete, more likely <br>wrong, possibly very dangerously wrong. Decompression develops out of both <br>physics and medicine, and, as such, must equally be regarded as empirical <br>at the core. This means that you cannot ignore practical experience in <br>discussion of decompression theories. Your hypothesis, that 36/80 deco is <br>just as good as 50/100, flies directly in the face of the WKPP experiential <br>database, and must, by the fundamental rules of empirical science, be <br>discarded or modified.</blockquote> There empirical database could only hope to validate 50/100 decompression, <br>and in now way allows comparison with 36/80 statistics that do not exist in their <br>database. It would also fly in the face of common sense to condemn another <br>approach to decompression on the absence of similar test data. <p>Yes they could provide guidelines, and statistics on using 50/100 deco <br>with a certain confidence level, no question. It does stop there. They do <br>not have the empirical data to compare with other options or decompression <br>schedules unless they undergo comparable field studies. Again, that seems <br>to be acceptable from an auditor's point of view. <p>A final point on the debate regarding theory and empirical models. We know <br>for a fact that all applied sciences strive to perfect models that apply to <br>the real world with a certain level of confidence, and with a certain level <br>of computational efficiency. It is rarely the other way around. <p>The human race used to take centuries to build monuments, and the effort <br>was often one of trial and error. Today, we errect structures that are true <br>modern day monuments, and we do this in a matter of weeks. Likewise, we <br>have a rather high level of expectation on the durability and reliability of <br>those structures. Would it be acceptable to you to hear every evening, <br>on the six o'clock news that another skyscraper just collapsed? Is this <br>crystal clear? Can we all make the leap here? We cannot wait for a person- <br>century of experience to cut a decompression schedule. We must have <br>models that will, within reasonable bounds of confidence, take us to and <br>from where we want to go, and we must do this between the time it takes <br>to blend, and the time it takes to get ourselves to the site. Are we all on <br>the same page? <p>At the end of the day, to every diver on the face of the planet, it is the <br>model that will be of prime import. Dependence on a single decompression <br>strategy negates flexibility, and could prevent someone from diving <br>given (other) logistical constraints. Flexibility is again paramount. <blockquote TYPE=CITE> <p>NOW, if you had instead advanced the statement that "Existing theory says <br>that 36/80 deco should be just as good as 50/100, maybe a little better, <br>but practical experience shows in detail that this is not so, and therefore <br>we need to refine the theory", then this particular flamethrower party <br>would not be happening.</blockquote> <p><br>That's a roger John. I must say that the needle that broke the camel's back <br>was indeed the statement that 50/100 was better, and if you just look at <br>the residual tissue numbers... Human nature, after that statement, well, <br>I thought that if things were getting this silly, it was high time we aired <br>all the dirty laundry. <p>It could have been less messy, but this is hopefully stimulating, and will <br>prevent folks from going in with blinders on. Some of the "myths" were <br>a hazard, and it is important for people to realize the implications of <br>what they are saying. Details do count in this business. <p>We collectively accept the algorithm calculating as if it was 100% O2 <br>all the way, but do we stop and think that we're not doing that? Tell <br>me that doesn't matter. <p>We collectively think that taking breaks from pure O2 decompression <br>increases lung efficiency, that's wrong. Taking breaks curbs lung damage, <br>possibly prevents it, and mitigates decreased lung efficiency. Why do people <br>have this false assumption that lung performance is somehow enhanced <br>by taking breaks from pure O2 breathing. This is just another dangerous <br>myth. Yet we accept these things, and we even berate people for pointing <br>these realities out. Double expresso here, coffee just isn't cutting it! <p>This will be of service, maybe a bitter pill, but that's life. <pre>-- Guy</pre> </html> --Boundary_(ID_CS6AibwRPT3BIxLSG4IuLg)-- -- Send mail for the `techdiver' mailing list to `techdiver@aquanaut.com'. Send subscribe/unsubscribe requests to `techdiver-request@aquanaut.com'.
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