HPT3 once bubbled...
One of the first statements my instructor made to us was "We want you to have fun in this class." Stressing the importance of the dangers of diving was not on the top of the list.
20-30 years ago, diving was different than it is today. Diving was regarded as something of an extreme sport (although long before that phrase was coined) and a reasonable amount of fitness and mental acuity was assumed to be required. If you lacked one or the other you didn't pass and nobody babied you through the course.
Even basic open water certification classes required fair amounts of math and the ability to calculate things that are today not even touched upon in Advanced Open Water classes. In AOW classes deep diving meant 130 feet and deco procedures were routinely taught by instructors. Students in general got enough theory and training to go forth and advance to more "technical diving" (again well before that term was coined) pretty much on their own by informally mentoring under other more experienced divers. The sport was more dangerous in some ways, but then that, along with the greater challenge of the sport was a large part of the attraction.
Then the earth cooled and the dive industry discovered marketing. The training agencies watered down their curriculums and the equipment manfacturers found colors other than black, blue and orange and focused on style to a greater extent in order to attract more females (who unlike most males understand that orange is really a rather yuckky color and is hard to coordinate with nearly anything else). Both facets of the industry were driven by the potential to attract and produce large numbers of very casual and minimally trained divers who made up for a lack of skill and ability with money, credit cards and a desire to travel once or twice a year.
Of course the problem with this new approach was that you could not do serious stuff in training like emergency swimming ascents with students who can barely swim and you could not do it with a large number of students without statistically getting increasing numbers of people hurt during training or afterwards which, after all your efforts and advertising to the contrary, would lead people to view diving as dangerous and cause them to do something else with their money and over extended credit.
Consequently, attracting large numbers of people required that the danger be taken out of the sport and focus of dive training changed accordingly and stressing the dangers inherent in diving is not considered real cool in a modern scuba course.
So learning to dive got easier and the agency approved limits for open water and AOW divers got tighter to protect poorly trained and usually infrequent and minimally proficient divers from themselves. The strategy has however worked as diving is statistically safer than ever for the average recreational diver even if their skills are pretty limited and it's rare to get more than 0a dozen dives a year.
Following this industry change in direction, a split developed as the hard core od school divers continued to go deep and continued to do things like deco and overhead diving in wrecks and caves. Along with this they developed well thought out approachs to equipment and began using really wild (and according to the dive industry irresponsible) technigues and exotic gases like nitrox, which even 15 years ago would have gotten you kicked off many if not most dive boats.
The dive industry did not accept the newly fledged tech community until sales to normal divers flattened and the marketing folks who gutted the sport as it existed in the first place made the discovery that a very small percentage of divers (the technically oriented folks) were responsible for an unusually large percentage of the total equipment sales.
Then they got the brainstorm that if they reversed their position and said nitrox was a good thing and not some sort of lethal devil's brew, that they could make a killing on nitrox certification courses and then really rip everybody off by requiring specialized regs for use with nitrox.
So in some respects I think the recent rise in interest in technical diving and technical certification courses is sort of a natural correction to some of the negative things that have happend in the current dive industry's watered down open water and AOW training. It also provides a greater range of freedom and opportunity for a minority of incoming divers today who are in most respects very similar to the vast majority of divers in the sport 20-30+ years ago who enjoyed diving as a challenging and demanding sport with a user adjustable level of risk.
Having said all that, I agree that doing emergency ascents is a real confidence builder and that actually doing it in training is probably the best way to condition a response in a diver other than blind panic when the air stops flowing. But given the wide range in swimming ability and other water skills in todays new breed of recreational diver I am very hesitant to make a blanket recomendation to practice it.
If you can free dive to 30 feet in open water, you would, with proper training and supervision, have no problem doing a free ascent from twice that depth at a safe ascent rate. But if you feel challenged getting to the bottom of a nine foot swimming pool it's another story entirely.
