I will not debate the merits of deep air because I think diving to depths beyond recreational limits on air is not smart. I also don't feel that there is a great tolerance to be aquired other than being better able to deal with intoxication which is no smarter than learning to drive a car after a 6-pack.
Pretty safe to say we are definitely on the same page here. My understanding is that the decision to make 130' the "recreational limit" was a rather arbitrary decision and had nothing to do with narcosis. Moreover, one could make the same argument that choosing 100' as a max END is also an arbitrary decision. Is .08 or .06 blood alcohol content the limit beyond which we can operate safely? The current science pretty clearly shows that narcosis starts as soon as you enter the water and then it becomes a matter of how "much" narcosis we should tolerate. Personally, I have a zero tolerance for drinking and driving and apply the same conservative standard to my diving. Further, I think we could agree that 130' in our neck of the woods is sure not the same thing as 130' in say, anywhere in the caribbean. However the fact remains that physics is physics and the gas laws are what they are, regardless of whether we are in the Caribbean or the PNW. The only real difference becomes one of perception and this has nothing to do with the actual physics of the situation.
Again it all comes down to a personal risk analysis. My personal decision is not to push my END deeper than 100' and I chose to take the additional training necessary to develop the skills necessary to dive with trimix. I also chose to make the commitment to a regular training and fitness schedule to keep those perishable skills current. What other people do is absolutely up to them, but my choices were what they were. I guess you have to draw the line somewhere and 100' makes a nice round figure to calculate gas consumption based on ATA's, as well as simple gas strategies using nitrox on depths less than 4 ata's. Again, everyone is entitled to their opinion and I don't intend to try and convert anyone who choses to disagree with me. I have been on dives where the C02 build up became problematic as a result of fatigue, coupled with poor viz and current. This made for some uncomfortable diving in warm and sunny climates and at very close to 100'. Again, I will base my decisions on the latest science coupled with personal experience and I don't let economics play any part in those decisions. If I can't afford to dive mix for the dive I want to do, I won't do the dive. Pretty simple and not unlike my decision not to drive or get in the car with someone who has been drinking at all. Just a fairly conservative approach. If I can't afford the taxi home from the bar, I would walk or call someone, but just because I didn't have the cash for the taxi I still wouldn't drive. I just chose not to put myself in a situation where my only options are all poor decisions. Dave, like you, I have a military background and one which developed a very strong proclivity to details where if we screwed up, someone's faimily was getting a letter from the CO. I don't ever want my loved ones to get one of those letters.
As to your direct question as to whether I consider dives deeper than 130' to be deep air dives, for the reasons mentioned above, I am not familiar with a standard definition of "deep air" that everyone agrees on. However, more to the point, I do consider an END of 130' to be deeper than I or anyone else should use. Again, just my opinion and I chose 100' for my max END for the reasons above and not just because any particular agency pulled it out of the hat.
