In the case of activities like saturation diving (or in my case, firefighting), experience matters a hell of a lot more than all the PhDs in the world. After hundreds of dives (be it in smoke or water) you've seen just about everything that can go wrong, and you're in a much better position to break the chain of events leading up to a disaster.
You can argue about the hubris involved in the Columbia or Challenger disasters, but in the heat of the moment, I would trust the person who has trained their entire life and was selected from a pool of thousands for their supreme skills, talent, and temperament. These are not nervous nelly academics we're talking about here.
It's insane how prepared they are. In fact, it was hard for me to learn many lessons from the book, because the astronaut experience is so different from every day life. I just don't get to try things 1000 different ways and debrief with fellow geniuses every time. Real life seems to involve quite a bit of muddling through with barely adequate experience.
A good read if you want a glimpse into the mind of the ultra-high-achiever, crazy work ethic, moustachioed Canadian hero.
https://www.youtube.com/watch?v=YcSduoKj6KU