... I never saw any one mention no matter how well trained and what rescue skills it still comes down to what the person actually does in a rescue situation
When reviewing this story, I found it difficult to believe that either Gilligan or his Buddy were
ever properly trained to dive. Perhaps the Buddy forgot his training, but I find this unlikely.
I suppose it's possible that a Skydiver with a solo certificate could jump off the top of a tall building without a parachute. I do believe however, that even if it was a few years since his last jump, that he would know that what he was doing was technically flawed. That may not stop him from doing so, but it isn't because he doesn't know the rules of Skydiving, or gravity.
Recreational diving isn't brain science. People require three primary things to do it safely: proper and inclusive training (which may be mitigated by supervision), well maintained equipment and the application of common sense. If any of these are lacking, you can't blame one on the other.
Generally people who get trained do so in the attempt to do it safely (the application of common sense). As they have no point-of-reference, they depend on their Instructor to quantify what this is for any given diving environment. Instructors are led by the certification agencies and often influenced by the LDS (which at times eschews the definition of proper training). If time passes so as to place an individual in a situation where they have forgotten, they will likely seek-out instruction for the same reason that they did in the first place (it makes sense to them; they believe that this is a requirement).
I don't believe that the majority of "poor diving skills" are attributable to "forgetting how." I believe that many of these certified divers just haven't been taught correctly. Too many are certified before the Standards of the certification Agency have been met. Too many Divers that are certified to dive "unsupervised" simply don't have the training or experience to do so. It's not consequential that two of the World's oldest and most respected diving Agencies take the same position.