No bashing, your perspective is very common among recreational divers due to highly abbreviated US-centric training and liability constraints. As for “everything that's known and published”, I suggest you broaden your reading. For example:
US Navy Diving Manual Rev. 6 with Change A (red emphasis added):
Mild symptoms, like those that begin to appear about 130', are often very subtle and can go unrecognized. I contend that you don’t learn anything from Narcosis symptoms that aren’t recognized — which is the original basis of my comments in this thead.
This is not to bash to new divers. Think about what a foreign environment diving really is. Divers are in a media that they can’t breathe, buoys them up enough that they can fly (similar to zero gravity but not quite), colors and sounds are attenuated, heat conducts about 25x faster, plants and animals are unfamiliar, and most are covered head to toe with an strange collection of hardware. Of course we are distracted, like texting while driving. Symptoms of distraction and sensory overload are often attributed to Narcosis… except the exact same things often happen in 20' of water, especially to dive students. Throw in the random stupid things that all humans occasionally do and you have a perfect storm for misdiagnosis… “Honest, I’m not that stupid so I must have been narked”. Hmm, I might have used that one once or twice.
Narcosis is an easily scapegoat for other complicating factors on deep air. Higher respiratory workloads due to gas density, elevate PPO2, an often greater equipment burden, plus all the normal stressors of diving all play a part.
I have read the stupid-drunk stories like this since getting a copy of Cousteau’s The Silent World in the mid-1950s. I suspect this quote was “adapted” from earlier works:
Chapter 2: Rapture of the Deep, page 31 of my copy:
We all know that isn’t the first stage of Narcosis, but call it literary license. It might be close to the hallucination stage at 10 ata. No reputable source suggests that the extreme symptoms that can occur in the 10 ata (+/- 300'/90 M) range happen at 130' or even 165'. Unfortunately, that is the impression too many divers are left with — arguably by design.
I cringe when the alcohol analogy is used to describe Narcosis. Nearly everyone with real experience with Narcosis describes their impairment as being quite different from Booze or drugs. However, it is an academic argument.
My point is that Narcosis isn’t the boogeyman that sea stories suggest nor is it benign. It is just another factor in the environment that divers must master to manage risk.
What really matters is that each diver learns about Narcosis for themselves rather than from conflicting stories or what others seem to do or avoid. The formula is simple. Make as many dives as you want to a benign depth like 60'/20M and start adding depth in small increments. Stop adding depth when you feel you are approaching the limits of your comfort zone. Whatever that depth happens to be, it isn’t something to be ashamed or proud of. Still want to dive deeper? Then take Trimix and related courses. Of course all the issues of decompression diving plus ensuring adequate and reliable breathing gas must also be mastered.
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