Place of dive tables in modern diving (Split from the basic thread)

[stuartv]

Educational value
Everything else aside - using Min Deco (and/or Ratio Deco) in a training setting offers a highly potent teaching opportunity and tool.
One may not like it for anything else, but this is one single point that I honestly think is damn well near indisputable.

I would not dispute this. It does seem to be a tool with high potential for teaching.

But, it seems to be me (as someone who does not teach tech), that a tool like the dive planner is Subsurface is better. I mean, I think it offers everything MD/RD offers plus it additionally offers a very visual representation of what is going on as dive time and/or depth increases. Different people learn in different ways. Having this visual component addresses learners for whom "seeing is believing". I think some people learn in a way that having this visual component will facilitate them to actually learn what they would otherwise not really "get" even though they may be able to perform rote exercises to achieve the "correct" answer.

Using the dive planner tool in Subsurface to the same or greater effect seems to me to simply be a matter of constructing the correct exercises for the students to perform in conjunction with the right questions asked of the students.

And, since it is a well-defined algorithm (assuming you use Buhlmann w/GF in Subsurface), you can actually assign exercises and questions and have 100% objective means of assessing the students' results.

 

[tursiops]

I would not dispute this. It does seem to be a tool with high potential for teaching.

But, it seems to be me (as someone who does not teach tech), that a tool like the dive planner is Subsurface is better. I mean, I think it offers everything MD/RD offers plus it additionally offers a very visual representation of what is going on as dive time and/or depth increases. Different people learn in different ways. Having this visual component addresses learners for whom "seeing is believing". I think some people learn in a way that having this visual component will facilitate them to actually learn what they would otherwise not really "get" even though they may be able to perform rote exercises to achieve the "correct" answer.

Using the dive planner tool in Subsurface to the same or greater effect seems to me to simply be a matter of constructing the correct exercises for the students to perform in conjunction with the right questions asked of the students.

And, since it is a well-defined algorithm (assuming you use Buhlmann w/GF in Subsurface), you can actually assign exercises and questions and have 100% objective means of assessing the students' results.

All excellent points.
By the way, when my wife teaches tables she uses a credit card analogy: if you don't pay it off, you can't charge to the card's limit. Nitrox increases your limit a bit.

 

[stuartv]

All excellent points.
By the way, when my wife teaches tables she uses a credit card analogy: if you don't pay it off, you can't charge to the card's limit. Nitrox increases your limit a bit.

That seems like a really excellent analogy for teaching that concept!

 

[Dan_P]

Since in 20 years of diving the only person I have ever seen try to use the RDP for diving is myself, and that did not work because we were doing multi-level dives, I am not an advocate of using it for dive planning. However, the RDP excels at something far, far beyond Min Deco. It was developed as a result of thorough research using Doppler bubbling imgain in thousands of dives and divers. That research as led by scientists of the highest repute.

Min Deco was developed by. whom after what studies?

By the logic of the statement above, one may as well be advocating 18m/min ascend rate because that's what's used in "thorough research using Doppler bubbling imgain in thousands of dives and divers ... led by scientists of the highest repute" [1].

Textbook Authority Bias, á la Milgram.

What's really at play here is one can't make things right and wrong by reference to authority, no matter how much one might like to make UTD and everything they touch into a whipping boy for the sake of one's own personal gestaltic conceptions.

Further, one can't very well make that argument for Min Deco without obviously having to also make it for every single computer algorithm and setting.

The quote above is but a sentimental non-statement.

Now if we all don't mind, I think it'd make sense to circle back to the matter at hand, RDP, and possibly the points I actually did mention in my post.

My argument is that in all matters application, RDP is inferior to either Computer or Min Deco, or both.

[1] Hamilton Jr, RW; Rogers, RE; Powell, MR - Development and validation of no-stop decompression procedures for recreational diving: the DSAT recreational dive planner.
Development and validation of no-stop decompression procedures for recreational diving: the DSAT recreational dive planner.

 

[stuartv]

By the logic of the statement above, one may as well be advocating 18m/min ascend rate because that's what's used in "thorough research using Doppler bubbling imgain in thousands of dives and divers ... led by scientists of the highest repute" [1].

Textbook Authority Bias, á la Milgram.

Putting aside any appeal to authority, what about the point of having tons of data to support use of, for example, the Buhlmann algorithm, or RDP?

How does the body of data behind MD/RD compare? Is there one? A body of data - and I don't mean anecdotal evidence.

I haven't really studied it, so the only body of data I've heard of is the Spisni study, which certainly did not constitute a recommendation for RD in my mind.

 

[boulderjohn]

By the logic of the statement above, one may as well be advocating 18m/min ascend rate because that's what's used in "thorough research using Doppler bubbling imgain in thousands of dives and divers ... led by scientists of the highest repute" [1].

Textbook Authority Bias, á la Milgram.

No, actually that is a perfect example of what I am talking about.

The 18m/60FPM ascent rate was chosen for the RDP because that was the standard rate used by just about everyone then, including the US Navy tables that were the norm then. All numbers on the RDP were based on that. That ascent rate, however, was not determined through the use of any real science. The story of its beginning is almost funny. Subsequent studies have suggested that 30 FPM seems to be much better.

PADI cannot officially change to 30 FPM for the RDP, though, because the numbers are based on 60 FPM. However, the research they did showed that those numbers are safe given that ascent rate. People are free to ascend more slowly, but the numbers will be a little off for them--although probably not enough to make a real difference. In its modern courses, PADI tells students using computers to use the rate for which their computer was designed, which is pretty much always 30 FPM.

In summary, when scientific studies show that a past practice is not optimal, practices should change.

So, back to my questions.

Who invented Min Deco?
What scientific studies were conducted to determine it is a superior system?

 

[Dan_P]

I would not dispute this. It does seem to be a tool with high potential for teaching.

But, it seems to be me (as someone who does not teach tech), that a tool like the dive planner is Subsurface is better. I mean, I think it offers everything MD/RD offers plus it additionally offers a very visual representation of what is going on as dive time and/or depth increases. Different people learn in different ways. Having this visual component addresses learners for whom "seeing is believing". I think some people learn in a way that having this visual component will facilitate them to actually learn what they would otherwise not really "get" even though they may be able to perform rote exercises to achieve the "correct" answer.

Using the dive planner tool in Subsurface to the same or greater effect seems to me to simply be a matter of constructing the correct exercises for the students to perform in conjunction with the right questions asked of the students.

And, since it is a well-defined algorithm (assuming you use Buhlmann w/GF in Subsurface), you can actually assign exercises and questions and have 100% objective means of assessing the students' results.

Sure! I mean, in a classroom setting it definitely makes complete sense to use a visual representation that depicts what's going on theoretically. A planning software can be a very fine choice, I think.
In terms of the training applications, the reason I like RD/Min Deco is because of the in-water use. There, however, it makes sense to not have any "assistance", for full utility.

 

[tursiops]

My argument is that in all matters application, RDP is inferior to either Computer or Min Deco, or both.

I'm sorry, but I find your arguments for Min Deco to be non-compelling, and more like advocating voodoo than anything science-based. You are very articulate, but you are also very much cherry-picking what you like or don't like or the evidence you are willing to accept. You mention Authority Bias; how about your own Confirmation Bias? I'm seriously tired of your continually selling the UTD line. You ought to be paying royalties to ScubaBoard. You are not discussing, you are preaching.

 

[Dan_P]

I'm sorry, but I find your arguments for Min Deco to be non-compelling, and more like advocating voodoo than anything science-based. You are very articulate, but you are also very much cherry-picking what you like or don't like or the evidence you are willing to accept. You mention Authority Bias; how about your own Confirmation Bias? I'm seriously tired of your continually selling the UTD line. You ought to be paying royalties to ScubaBoard. You are not discussing, you are preaching.

Now just hold on for a second there;
I'm saying I think computers and min deco are better options than RDP, and why.
It's easy to just say that's preaching, but I'm approaching the RDP-question in a fair fashion here.

If you don't agree with the points I make on the topic at hand, of course it's fair to make a counterargument, but it's not fair to start shoehorning me into the role of some preacher when I'm saying I don't think the RDP is a strong option, and clearly argue why.

 

[tursiops]

Now just hold on for a second there;
I'm saying I think computers and min deco are better options than RDP, and why.
It's easy to just say that's preaching, but I'm approaching the RDP-question in a fair fashion here.

If you don't agree with the points I make on the topic at hand, of course it's fair to make a counterargument, but it's not fair to start shoehorning me into the role of some preacher when I'm saying I don't think the RDP is a strong option, and clearly argue why.

You'll need to back further away than that. You have innumerable posts preaching for Min Deco.