Then our dive master reached out and pushed her down a foot, and suddenly her tank could clear the top. From her perspective she kept swimming lower, but that was counteracted by buoyancy and she couldn't tell, with every failed attempt reducing her mental capacity to figure it out.

Fight or flight is not the reflex we need in diving, but it is the reflex we have.

As one of the rescuers said, "When it starts raining the flow is so hard you can barely swim against it." - and that's a pro diver, imagine how would it be for a boy who didn't even know how to swim and thus doesn't have the relevant muscles trained. It's also narrow enough so that only one person can fit through, so you can't have the divers guide them by hand, only accompany them behind them.

I think they would have them tied to a rope between divers, so that one of them can pull (gently, in narrow areas) and the other can guide the package to prevent it from scratching the rocks.

And DIY versions abound: https://hackaday.com/2017/07/02/the-almost-working-diy-under...

> Narongsak explained that the divers had fixed rope lines along the passageway and distributed oxygen tanks along their route, allowing them to advance through the exceptionally narrow passageway unencumbered by bulky equipment.

The (extremely skilled) divers aren't wearing tanks due to how narrow some parts of the passage are. Using a thruster in a cramped environment is not a silver bullet.

It comes out later that the group frequent this cave many time before.

I know nothing about that cave, but passages between caves can be connected by tight restrictions. They might have crawled they way up. And now that restriction is flooded.

Even a semi experienced diver is far less aware of all their apparatus than a human who has been crawling around things since birth