I believe NAUI characterizes deep dives starting at 60 or 65 feet. As for using a deep dive in order to "get narced," I find that highly objectionable, and it certainly has not been a component to any dive instruction I have received or taught. I think the Navy makes it part of their program, but that's it.
From what I recall narcosis effects vary from person to person just like DCI, and can occur at any depth (the effects are simply known to increase with depth). The recent results quoted from the Croatian study would be the first substantial thing I've yet heard, but I'd like to know what the details of their tested personnel (age, demographic, physical condition, etc.). In any event I would be very loathe to take a class down deep for the purpose of "learning them" the pitfalls of narcosis. I could just see the lawyers swarming in if an accident happened. You'd need some super hefty waivers and Johnny Cochrane.
From what I recall narcosis effects vary from person to person just like DCI, and can occur at any depth (the effects are simply known to increase with depth). The recent results quoted from the Croatian study would be the first substantial thing I've yet heard, but I'd like to know what the details of their tested personnel (age, demographic, physical condition, etc.). In any event I would be very loathe to take a class down deep for the purpose of "learning them" the pitfalls of narcosis. I could just see the lawyers swarming in if an accident happened. You'd need some super hefty waivers and Johnny Cochrane.