  This paper asks and answers the question of whether Kahneman's planning
fallacy or Hirschman's Hiding Hand best explain performance in capital
investment projects. I agree with my critics that the Hiding Hand exists, i.e.,
sometimes benefit overruns outweigh cost overruns in project planning and
delivery. Specifically, I show this happens in one fifth of projects, based on
the best and largest dataset that exists. But that was not the main question I
set out to answer. My main question was whether the Hiding Hand is "typical,"
as claimed by Hirschman. I show this is not the case, with 80 percent of
projects not displaying Hiding Hand behavior. Finally, I agree it would be
important to better understand the circumstances where the Hiding Hand actually
works. However, if you want to understand how projects "typically" work, as
Hirschman said he did, then the theories of the planning fallacy, optimism
bias, and strategic misrepresentation - according to which cost overruns and
benefit shortfalls are the norm - will serve you significantly better than the
principle of the Hiding Hand. The latter will lead you astray, because it is a
special case instead of a typical one.
