I would hazard to say that one could learn a tremendous amount about gas management from books or online. Is there really anything about gas management that one could not learn from a book or online? I know the calculations are in books and online. I know the rule of thirds is in books and online. I know the decompression tables are there. I know there is plenty on partial pressures and oxygen toxicity. Even the explanations of the "whys" and "wherefores" of gas management are there.
Yet our heros seem to have perished due to poor gas management.
Now, it could be that our heros ran out of gas while dealing with some other problem, such as getting lost, but I have seen nothing suggesting that. So I will assume it was just poor gas management, the one easy thing they could have learned pretty well from books or online. My conclusion is that they probably did not even do the book or online learning.