Right. You bring up two aspects of the book that I should have.
1) The premortem thing is fucking awesome. For those following along at home, this is basically where the same team that put together your brilliant idea that can't fail is assembled in a room and asked "Okay, so how did this all come apart so catastrophically?" before any real money is spent or any real effort is invested. The idea is that the people who came up the smart ideas might be suffering from "ideological blindness" right when you need them the most and if you get them to forecast the cockup they've been working against, not only will they start thinking about stuff they might not have considered, but it's pretty much righteous fun.
2) I think things started going pear-shaped when Kahneman congratulated himself proving mutual fund managers are no better than blind luck. This is hardly a revelation. Further, when a manager told him in the car "I made my company a lot of money" Kahneman chortled to himself. Nate Silver made the point that the only way to beat the market long term is insider trading - which is also not a revelation. In other words, there were two people in that car and one of them thought he was describing a "market" instead of a "racket."
And really, that's the thing about the book - it's written from the point of life-as-Game-Theory. None of the messiness is ever investigated. Corner cases do not exist. Everything is a bell curve, and that's all you need to know.