An amazing story to hear what was necessary to recover the two dead divers' bodies and that it was pulled off without further tragedy. All good merit to those who made up the recovery team - both underwater and in support on the surface. This was the right thing to do given the two key rescue divers had good knowledge of the dive and the necessary experience and confidence to cope with the demands of the situation.
Rick Stanton suggests through his remarks and experience during the initial recovery operation that these sort of accidents do not need to happen. Who knows how the first diver became tangled in the line, but he should have been sufficiently trained for tackling such a serious length and depth of dive to be able to remain cool in such a situation and successfully change mouthpieces underwater - without a second thought. The fact that he was unable to resolve the tangle or change mouthpieces suggests that he was diving beyond his capabilities.
There is no explanation given as to why the fourth diver died or what steps may have been taken to assist him.
It all points to keeping your diving ventures within your training and capabilities, but even then the unexpected can still happen and things go wrong, so good training and prior preparation, thinking through all possible eventualities, is everything in this game of life and death . . .
And I've Rick to thank for assisting me out of a dark spot, once, back in 1984 - fortunately not underwater so time (just) and a cool head was everything for surviving the unanticipated situation. Prior to this, once, I 'pinged' my legs round a tight left-hand bend in a tight passage and knew I'd have to find bigger passage ahead to be able to turn round to get back out again. However, I found instead that the passage ahead got smaller and more awkward and that there was nowhere to turn round. There was no one else to help or who could have helped in this situation.
Based on my previous experiences in tight places, I 'sat' on the rising panic and kept it in check 'at arms length'. Even then you still had to calm your mind down enough to think through the situation clearly, to get yourself safely back to base, out of the problem(s). It becomes a "tackle the problem 6 inches at a time" situation and don't contemplate the consequences of getting it wrong. Once you're through the crux of the difficulty the relief is gradual, but then, suddenly, tremendous.
This is what you have to be able to do in a tricky situation underwater, when encumbered by diving equipment with the clock of your air supply ticking away, otherwise you should really be doing a different (easier) dive or a different activity altogether.