Interesting but not really actionable. The part about ditching weights seems a bit confused. Ditching weights underwater is seldom a good idea and will more often make the situation worse by causing an uncontrolled ascent with the associated risk of lung injury. It's more important to ditch weights at the surface; in many fatal incidents the victim reached the surface but then failed to establish positive buoyancy and sank again.
In my opinion trying to do any sort of statistical analysis of dive accidents is rather pointless. It's a lot more useful to do rigorous qualitative analysis of individual cases.