One of my skiing friends forwarded this good summary on how our built-in decision-making heuristics can create risk-assessment traps. If you care about risk assessment, the paper it cites is very much worth reading. Another skiing friend, who has a PhD in the psychology of decision making and does a lot of backcountry skiing and mountaineering notes that such retrospective studies are interesting but have to be read with some caution as they may have limited predictive value. Nevertheless, until more controlled studies happen — unfortunately not likely, funding is hard to get — that's all we have to go on. Incidentally, much related territory has been covered with respect to economic and financial decision making in the aftermath of the financial crisis.