I suggest reading the book "Shadow Divers" for a look at some of the professional diving culture. It's super interesting. This death is definitely horrible. However, reading Shadow Divers also made me think that any cave divers take on high risk every time they swim, and that this death - while tragic - is a risk this person confronted long before the incident.
Just wanted to point out that diving culture as described in 'Shadow Divers' is pretty much as far from professional as it gets. What the book does describe is east coast deep wreck diving community of the early 1990s. In which I suspect it does a good job at. And how they pushed the limits before mixed gas diving / non-open circuit scuba equipment was well understood or widely available outside military and possibly some commercial outfits.
That said, the book is great read. Especially if you're into diving. It's just that it should not be read as a role model for anything but reckless regard of ones life.
Not to drift completely off-topic, here is a link to a long thread about Thailand cave rescue from the cave diving forums[1].
