... Am I just totally missing the point here?
Yes you are.
... I'm a new diver and maybe I have the wrong opinion on this.
Yes you do. Go get your dive tables, re-read the chapter in your training manual on dive tables and repetive dives. Dives under 40 feet (NAUI) or 35 Feet are counted as dives to 40 or 35 feet respectivly and do have limits. Do the math and then come back and tell us how this is within the limits of his training and certification agency guidelines. Remember in SCUBA we round up, not down for safety when it comes to depth and bottom time and round down for remaining air (1950PSI is 1900 PSI)
...I'd like to think that the majority of those issues happens ...
Key word majority. That means there are people (the miniorty) that stuff happens to. Example, my daughter, who had been married 2 years at the time and going to college, was on the pill. The pill is 99.9% effective. That means there is a 0.1% chance of getting pregnant. That would put my daughter in the minority as the majority do not get pregnant, but she did get pregnant on the pill and is now a mother. So majority does not cut it, stuff happens to the minority and if you happen to the the minority, life can be cut short.
Oh, and suggesting you won't get that kind of bottom time on 4 110 tanks is crazy at 30'.
Not suggesting he can't get 1 hour 15 on a dive. I have done 90 miutes or more on AL80 on dives that went deeper than 40 feet. I am suggestesting that he might get bored (lake diving) and chilled and maybe tired and maybe actually remember his certification training and abordt after 3 or 4 dives. Frankly I think your friend is pulling your leg. No, you can't stop him, nor are you responsible for his decisions. Sometimes you have to remember that you can't fix stupid and the ocean does clean out the gene pool from time to time. You
can do the right thing and not let him talk you into something stupid like joining him.
True these are shallow depths and if he is diving a dive computer he will be allowed more time under because he will be charged with his actual depth and time (guessing he is at less than 20 feet most of the dive) and the computer may allow it. But that still leaves the no-fly rule. Can he do it? Maybe. Is it smart? No, it is not. You have to weigh the potential cost. Unlikely as it may be, but there is the potential for injury going from -30 feet to +8000 feet in less than 24 hours. So what is the worse that could happen? Could range from nothing to skin bends to, paralysis for life or death. Just make sure he remembers or his next of kin knows that 1: he was trained not to do what he did 2: he intentionaly ignord his training 3:He knew the risk.
Bottom line, each of us make and are responsible for our own dive decisions. Would I do 2 dives to 30 feet with 1 hour 30 minutes between them and then fly in 16 hours? No, I would not. But then I am old and there is a reason I have survived this long.