True, this was a vague topic. I'm interested because real life experience shapes us personally. For example: it took me a long while to respect hypothermia. The first two decades I called a dive if stage 2 symptoms moved to stage 3 (blurry). Now (I didn't log dives until 2 years ago) I refuse to be the slightest cold while diving, I want to be comfortable throughout the dive. So after a bunch of dives I realized my own insulation properties are below average and mental stubbornness isn't enough to counteract this biological fact.
Background:
I read a thesis interviewing the regional dive pioneers and some have been active 60+ years.
I hear 'you don't know what you don't know.'
Thirdly, I've observe how personal dive theory becomes to the more experienced divers (closer to 10,000 dives). Their own NDL (or deco schedule), SAC and equipment requirements seem to be far from typical.
Specifically, I'm interested in trying to see what experience has taught or what became real. The finer tuning that is true to you, but likely not true for everyone.
I am interested in the areas generic dive theory, standard equipment and typical OP becomes personal to you. Perhaps that's a little clearer.
Regards,
Cameron
Well.... a couple of things come to mind.
Time pressure
I've gone through a few phases where it comes to my understanding of decompression theory. I learned to dive in 1984 and the practice of diving near or over the NDL's has changed a lot over the years.
My initial training taught me to literally fear the NDL's. At the time we all dove with tables and there was little to no information available for sport divers about staged decompression diving. Technical diving was something very vague and made to sound very dangerous. As a result of this I initially felt under time pressure during every dive. This went on in my case for several years (and several hundred dives) until on a particular dive I took on what the tables thought of as a decompression obligation. It was an uncontrolled situation where a diver in distress needed rescuing. My buddy and I intervened but by the time we had him out of trouble and ascending we were very deep and "off the tables". Not knowing what to do or how many minutes of decompression we needed to do, we ascended and did "emergency" decompression by basically breathing the tanks down to empty at a shallow depth and then hoping for the best.
You would think that this experience would make me more fearful but it had the opposite effect. After having had that experience of being "off the tables" and having handled it, albeit clumsily in retrospect, I felt less time pressure in subsequent dives as long as I was not actually OVER the NDL. The next phase of that came when I got a computer. I didn't start diving with a computer until the late 90's but it seemed to free me of more of this feeling of time pressure because I knew that even if it did get over the NDL it would show me a ceiling. I still had, however, little idea of how fast decompression obligations build and how to handle anything non-trivial.
The final steps in dealing with this feeling were taken when I started doing technical training. The first time I did a planned decompression dive I felt an utterly overwhelming feeling of RELIEF to finally be rid of that nagging feeling of time pressure. After my first technical specialty I took a number of others. As my skill set grew I became more and more comfortable with what I was doing. These days I seldom make any dives within the NDL's outside of my role as a PADI instructor. Naturally as an instructor, I am motivated to tell students the truth about the NDL's so they don't have to go through the feelings of time pressure and angst that I did.
Handling an accident
I have the type of personality that if a fire were to break out and everyone was panicking and running away, I would be the one running toward the fire and trying to do something. As a teenager I was already teaching first-aid having initially learned it from a friend of the family who was a paramedic and my grandfather who was a WWII vet and worked ambulances and trained mine rescuers for a living. As a teenager we did "competition" first aid and my team won 1st or 2nd place when we competed. The teams I trained never got over 2nd place but competition was stiff
With that as background, I always wondered what I would do if I got involved in a real accident. I had taken control a couple of times at serious car accidents but that was all stuff that I had actually trained for in my first-aid training. The rescue course was good but a rescue scene is much bigger and harder to control than something like a car accident. You're delegating tasks on people you can't see anymore, you need a bigger dose of creativity and you can't keep the chaos down as well meaning bystanders try to "help" by doing all kinds of crazy distracting stuff. Despite my background in first-aid, I really doubted if I could handle managing an accident scene in a real-world rescue.
At least that was the impression I got from taking the PADI rescue course. As an instructor, that doubt was nagging and as a result I never taught the rescue course. I assisted with it many times but couldn't be 100% sure that what we learned was really going to work as advertised I wasn't willing to give that line to students if I wasn't 100% convinced. This is a case of being aware that "you don't know what you don't know".
Then 6 years ago me and my (dive) team got involved in a major full-scale rescue of a missing diver who went OOA on the bottom and was left there by his buddy who went to the surface to get help. Everything I thought would happen during a rescue did, right down to the guy who started in at my OW students, who were not even certified, that they needed to get out there and start looking for the missing diver.
I could write a lot about this incident but the main thing for this thread is that it completely convinced me that if an accident happens I can handle it and I can handle myself with the responsibility of managing it. In this case the diver who went OOA and was left on the bottom survived and recovered. This was good for confidence, of course, since it's probably one of the few such rescues ever to end well.
Now I am convinced that I could teach rescue with confidence. A few things in the course need to be tightened up a bit but you can do it within standards. The funny thing is that I haven't taught it since that accident at all. At first I needed time to give that experience some closure in my mind. It turned out that it had more a psychological impact than I would like to admit. I could do it now but I don't get around to it because I put 100% of my focus on OW students who are in more need of good instruction than rescue students.
R..