Spectre once bubbled...
Ok... first off... SAC rate calculations are all math based... you _can_ learn the math on the Internet. learning how to actually use the numbers you calculate as a basis for dive planning can also be learned outside of a scuba class [I'm not endorsing that, I'm just stating it's possible].
Now as far as the DIR-f goes, I don't completely understand the non-smoking requirement. A recommendation is fine, but a prerequisite for the course seems a little extreme. There are many things just as bad, or worse, than smoking. What's next? "Meat eaters need not apply"?
It just seems out of place IMHO.
Yes... smoking is bad. I don't think you'll find one [minimally intellegent] smoker that doesn't accept the fact that it's bad for you... How many smokers do you know that started smoking in their 30s, or 40s, when they were old enough to truely understand the risks, and seen the effects? I don't know any smokers that started smoking after they were 19. However it's shown that getting off nicotine is as hard, if not harder, then heroin! I've never been addicted to heroin, so I don't know for sure, but I'm sure it has to do with the really really hard part about quitting smoking.... which has to do with it's _everywhere_. It's nearly impossible to shelter yourself from seeing or smelling smoking while you try to quit.
Oh... O-Ring. Copenhagen won't work... it gets nasty when you spit into your reg, and your buddy'll probably kick your butt after a few s-drills!