MHK has given a good explanation of the reasoning behind the DIR position on computers. We all have reasons why we do things. As always, it's good to look at different perspectives.
If my understanding is correct the reason for discouraging computers is based on efficiency. They can fail, be misused, lead to dependency
All devices fail. Including the biological one in your head, which will not only fail but assuredly become impaired by depth, when the stress level goes up, fatigued, distracted, etc. Is using an instrument that will probably not fail, but provide you at a glance with the critical information you mentally calculate using a bottom timer and depth gauge - a liability or an asset? In addition consider that it is not subject to the physical problems
mentioned above. This device makes it easier to track, monitor, and understand critical information during times of diminished physical/mental capacity. Computers today are quite reliable, in the event one was to fail a trained diver could switch over to a backup system or safely abort the dive. Would you prefer to do mental mathematical calculations when it would be more appropriate and efficient to use a calculator? Just because I use a calculator when appropriate (more efficient) does not imply I cant do basic math. Just because I choose to use a device (dive computer) to track my dive profile because of its greater efficiency in performing this task, does not mean Im not aware of what is taking place and can't handle a device failure.
A computer provides me with important information at a glance, exactly what instruments and their display panels are designed for. They can enhance our monitoring capabilities or situational awareness when properly used, not diminish them, especially
during stressful times. Right now with nothing more than a glance, not every five minutes after Ive done a quick mathematical calculation, which is more likely to be wrong than the computer's more precise, and likely less error prone calculation.
When it is deemed that the user of a device has a tendency to solely rely on it, thereby creating a dependency at the expense of understanding what is taking place and the ability to manage a scenario where the device fails, appropriate measures must be taken. One of which is to discard or discourage use of such device. But this is only one option. Better training is another option. Improving the device another.
Furthermore, what is the likely consequence of discouraging the use of this device?. Many of the divers who are likely to not understand and misuse their computers are likely to be the same ones who have no desire to further advance their diving education and skills. These divers would probably be more likely to misuse the tables or mental tracking than a dive computer, since they are more difficult to operate and understand.
A dive computer inappropriately used may be better than the tables inappropriately used. At least the bells and red marks will give them a hint. These audible and visual alerts
that some dismiss as useless can assist the non thinking, and thinking diver, with very little effort on his part. Setting an alarm or a quick glance, something which the tables
and mental what? ...... do not so readily provide to many. You wont find the right answer unless you consider the user and environment. .
The one qualified advantage attributed to dive computers is the increase they provide in bottom time, or it could be said in diminished deco time. How do these devices accomplish this?
Precision. Quick, accurate calculation, beyond human capability.
But deco theory is not precise. Yes. But, big but, once you have chosen your deco model, take your pick which is best, another topic for another thread; the closer you know where you stand with respect to your chosen deco models theoretically safe
parameters is an advantage. The more accurately you know where you stand, the better informed you are facilitating making better decisions. Given that a deviation from the norm increases or decreases the probabilities of getting a hit, even though the exact factor is unknown, we can assume that the greater the deviation the greater the safety/risk is. With greater precision than other less precise tracking devices or methods one is able to
better conform or deviate from the models parameters by a known factor. A deviation which is cumulative and becomes increasingly important in repetitive multiday/multilevel dives. If I'm not mistaken I beleive I've seen DAN statistics which show that DCS is much more likely in repetitive dives. Although there are many factors at work here, and educations is a big one, knowing the precise degree of deviation from the deco model norm could prove significant.
As some have pointed out degree of deviation may be insignificant with respect to computer or mental dive tracking. This is largely dependent on the dive profile, averages only work well within certain confined parameters. A dive with frequent depth level changes, sometimes relatively large, over a lenghty period of time, would increase in imprecision as the data sample rate increases. Although it may not be wise to perform certain dive profiles, the fact remains that many do to some extent, and a computer will accurately track these profiles which would be impractical and less precise to track mentally.
In summation, negatives attributes are mentioned as to why computer use is discouraged. Comparisons are made ad hoc, jumping from one to another, comparing apples and oranges, in what I see as an attempt to support a logically insupportable conclusion. Deco theory is imprecise, deco models have a buffer zone, comparing a point of one model to another point of another. All equally applicable to any and all deco models Ive heard of, including the one proposed.
Most computer shortcomings can be attributed to operator error, operator ignorance, chance of failure, and deco model deficiencies. Many of these reasons are equally applicable to mental/manual dive tracking but are not mentioned as such, misleading some to reach the wrong conclusion that the proposed tracking method is immune from these deficiencies. Once again, we see only deficiencies pointed out with the intent to disparage something, without the mention of any positive attributes or mention of a scenario where the tool can be beneficial to those trained in its proper use. No negative attributes, only positive ones are presented or implied regarding the tool or method of choice, even when vaguely explained. Comparing the negative attributes of any device or method to the positive ones of another is a flawed analytical process which will likely result in a flawed conclusion.
I have not seen anyone propose a computer as a solve all problems, no thinking required, autopilot diving tool. Are computers necessary to safely dive? No. Are they a tool
offering certain advantages to divers? Yes. Is cost a factor to be consider by many? Yes.
One more point. This is a regulated public forum for the open discussion of ideas related to diving. Though undoubtedly anyone is free to pull from a discussion at any time for any reason, to begin one and then leave or claim foul (claiming insult, while not seeing how they insult others) when ones point of views are challenged or a more persuasive argument is proposed.is not a convincing way to prove a point. Taking the high road claiming liability, inappropriate forum, lack of understanding, complex subject matter, protecting self interests, dubious intent by others, etc., is all fine and good - but proves
nothing. This is a DISCUSSION forum. This is not meant for MHK specifically since he has mentioned valid reasons to not continue certain discussions any further, which I can accept and thank him for his contributions. But, when this same pattern of excuses is
exhibited by many other DIR proponents with no such interests in many discussions where their ideas are challenged - makes me go hmm? Why not carry an argument out to its logical conclusion, wherever it may lead? Too busy defending the right way to find
what may be a better way?
