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Jody,

You posted:

>Just a nit-pick; MiG Plan generates tables based on the Huggins and
>Buhlmann algorithms.  It is not accurate to say this person was bent on
>MiG Plan; he was bent on Buhlmann tables.  Some of the other programs have
>made changes to the models, and in these cases it may be somewhat accurate
>to say that a person was bent on them.  MiG Plan develops tables 
>faithful to the original design of the models, and therefore deserves 
>neither credit nor blame for the reliability of its output.  

I have to take exception with this statement.  If you run MigPlan with
"Normal" bias, then you are running the Buhlmann algorithm.  However,
once the diver/user chooses any of the "more conservative" bias settings,
then they are running something other than pure Buhlmann, they are running
a MigPlan modified Buhlmann.  Changing Dr. Buhlmann's "a" or "b" parameters
does constitute modifying the algorithm.  And, once the algorithm is
modified, relying on the testing done on the "pure" Buhlmann tables is no
longer valid.

Maybe we are just picking on semantics, but I do believe that by allowing
the user/diver to choose different conservative factors, that you have
departed from the "pure" Buhlmann algorithm.   Probably the only approach
to adding conservativism to the Buhlmann algorithm that essentially does
not modify the Buhlmann algorithm is using the next greater depth or
the next greater bottom time when planning the dive.

This applies to the other dive/decompression software out there that
makes the statement that the testing done by Dr. Buhlmann is all that
is needed to validate their modifications to the algorithm, but especially
to those that modify Dr. Buhlmann's parameters.

Just my opinion -

John
(johncrea@de*.co*) 

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