they thought would not be safe
That is a phrase that causes me a lot of frustration....it is very subjective, and often what society or a person deem as "unsafe" is in fact, less significant than other behaviors or diving practices that are "frowned upon" by some appointed group
A really fit person with the wrong attitude is probably
less likely to die diving than the "obedient" person that has
chosen an unhealthy lifestyle.....person A is just treated less favorably by the SCUBA dive community. You really see this when you compare the freediving community and the opposite judgements they make about divers (smokers, overweight, etc) I find the SCUBA community very paternalistic about people's "attitudes" compared to other instruction, which is ironic because it's not like you might land a plane on somebody's house. Imagine a rock climber or a mountain bike rider getting lectured about their "attitude"...not so much. The SCUBA community is pretty judgemental, I would say.
Managing your own risk is not encouraged by PADI, I'd say. I don't really know about NAUI, my cert was so long ago.
It's almost like Apple vs Microsoft. Jobbs says "we know best, and there is only one way to do it"....Microsoft provides some flexibilty, etc.