Actually, it was stupidity that did him in. I get along with the ground and gravity just fine.
Apart from the issues concerning the dissent, the need to be safer and train better better become part of the tree-sitter mantra, or potential recruits to do this sort of thing might become hard to come by.
The most dangerous period of time motorcyclists pass through is the point where they become overconfident after a month or so of riding beyond their actual abilities as a bike handler. Seems that this guy became too over confident too.
I would dare a guess he also had never gone through Army Paratrooper training too.