I will admit that this may be my inexperience (and lack of technical education) talking but I see your first example of "you may want to rethink how you plan to do that dive" as "Yeah you could do it that way but maybe there's a more efficient/more practical/simpler/whatever way." I wouldn't take that statement to mean "that's a bad idea that you shouldn't embark upon". I don't see that as a failure of understanding, but a failure of practical knowledge and application that allows the same thing to be accomplished in a more "elegant" way. That to me isn't a safety concern but rather an aesthetic one... but I may not be fully comprehending what your instructor meant.
... and that's a good example of what "you don't know what you don't know" means ... your interpretation is technically accurate, and practically meaningless. First off, my mentor was not an instructor ... he was a very experienced diver, one who used to post a great deal on ScubaBoard about the importance of thinking through your dive before you do it. What he was trying to tell me was that there were aspects to doing the dive safely that I wasn't considering... and that while I could do the dive as I was doing, a wrong set of circumstances could lead to serious consequences because I wasn't either mentally or physically prepared to deal with them. There were things about the dive I had not considered because they were beyond my experience, and not taught in class. And some things that were taught in class were being misapplied, because I had not really thought through WHY those things were taught.
Diving isn't so much about a right and wrong way ... or "elegance" as you put it ... as it is about making decisions based upon a knowledge of your limitations and how they apply to a given circumstance. Every dive is different, and when something goes wrong you need to be mentally, as well as physically, prepared to deal with it ... because the decisions you make are at least as important as the skills you possess.
An example, if I may, would be the young woman who followed her father into a cave recently and got lost in a siltout. She was skilled enough to maintain her cool and find an air pocket, and smart enough to remain there waiting for help. But while waiting she kept her fins moving ... because it never occurred to her that in the process she was making it impossible for the silt to clear so someone could find her. Except for an extaordinary effort on the part of her rescuer, she was effectively killing herself and didn't even realize it.
Application and theory, as you said, are often very very different. Getting a light-bulb moment is pivotal in most people's acceleration within a certain field and I grant that diving, like everything else, must be replete with these moments. I just don't happen to believe "You're going to die" is a way of making people understand that. Even with training, those moments don't happen just because (or when) you want them to and if you understand the theory after a class, the rest is the application, which is what diving is with or without an instructor. I just don't see much difference in learning the theory from someone else as being that much different from ingesting it on your own.
Most people, in moments of stress, don't think clearly ... they don't "stop, think, and act" ... they react. This is human nature ... and the true physiology of diving ... because it's often when the decisions are made that ultimately lead to a bad outcome. People decide to bolt for the surface because of a chronically leaking mask, even though they know perfectly well how to clear a mask ... or any number of common problems with solutions that they were initially trained to deal with ... because in a moment of stress they fall back on instincts that were never designed to keep them safe underwater. Or they make decisions prior to the dive that place them in situations they hadn't thought about or prepared for beforehand. Why? ... because they didn't know enough to think about them.
As for stress, you've exactly made my point. People who say "you don't know what you don't know" assume an awful lot of information about someone's non-scuba experience levels that just can't be assumed. I've said it before and I'll continue to believe (and probably say) it; stress management for scuba diving doesn't have to be learned by scuba diving. Stress management is very applicable across a lot of disciplines, if my experience is anything to speak from, which I am inclined to believe. It is, after all my experience (and my bias). Once learned it doesn't go away. Yes, it needs to be adapted, perhaps, from discipline to discipline, but that really only takes minor adjustments.
Stress management won't do you much good if you don't know enough to comprehend the appropriate response to a stressful situation. It can often lead to decisions that are completely inappropriate ... although seemingly logical ... to the circumstance. This is why, in reading many of the threads in the A&I forum, we read something and wonder why the person didn't respond in a way we would have ... usually it's because it never occurred to them that they should. There's a big difference between reading about a stressful situation and living it. I think you're underestimating the degree of adaptation needed to apply stress management techniques learned above water to a diving situation ... because ultimately it falls back on either relying on instinct or learned responses. And if you haven't taken the time to learn the appropriate responses, the instinct will cause you to react in ways that may work well in atmosphere, but are very dangerous underwater.
I agree, scuba diving is more than simple physics and basic math. That's not what I said, though. I said the theoretical education of planning dives and the information required to do that planning is basic physics and simple math. Literally, children can do it. Technical diving, while taking more effort to plan carefully, as far as I can tell, still doesn't require any further advanced math than figuring out mixes (which may be less trivial than I realize but I assume it's not significantly more complicated than figuring nitrox MODs) and deco times. I suspect making choices like which specific gasses to use and when is where the real art of technical diving comes and that most definitely is where experience takes on a major role. Kind of like using 2 different blends of Nitrox for a given depth and a time within NDLs for either mix. Why choose 32 when 30 will do? I don't know, but I suspect as I get more Nitrox experience I'll start to develop my own beliefs and reasons for selecting a given mix other than strictly following MOD and "house blend". I believe that is more in line with what your instructor example might have been hinting at, but as I said, I'm willing to concede that may be my bias and inexperience speaking.
That's an amazingly simplistic analysis that is so wrong I don't even have time to explain it to you (I have to leave in a few moments) ... let me just ask you to put that paragraph somewhere you can come back and refer to when you gain some more experience, and you can decide for yourself how accurate it is. Or perhaps I'll have time later to get back to this and explain it in more detail.
I like Thalassamania's "cone" description in the post following yours that I've seen him post a couple times. I think it's a very good way of describing the issue to people like me who often play Devil's Advocate (though not what I'm doing here) in this discussion as well as people who truly don't get why they shouldn't do a particular dive. (While I talk about the fact that I believe "formal courses" are often unnecessary I wouldn't even come close to making the kind of dives we're discussing.) It makes the concept of pushing your limits to the extreme very intuitive and gives a good solid concept that is applicable at whatever depth for understanding the level of added risk you're taking on during a dive.
Thal is the consummate educator, and I usually find his descriptions very cogent and applicable. But the fact is that most of us are very good at overestimating our skills ... and as a result, tend to push our "comfort zone" well beyond the cone without any meaningful internal feedback to tell us that we're well into the trouble zone.
That said, I agree with you that "formal courses" are not always the best answer. There are many skills and diving styles that I've acquired without the aid of formal training. I never push con-ed classes on my students ... preferring instead to encourage them to get out and dive, and contact me when they feel that they want to take their diving to the next level. Better yet, let's just go diving. Sometimes the most important lessons you'll learn ... and the most useful skills you'll acquire ... are gained simply through experiencing a given circumstance in the company of a more experienced diver, and following their lead in resolving it. Formal training classes are artificial environments, and usually won't put you in those circumstances ... and it is often the case that the most useful classroom is out there with your dive buddy. The key is maintaining a reasonable understanding of where your limits are, and not pushing yourself into dive plans that exceed them beyond your ability to deal with the unexpected.
... Bob (Grateful Diver)
