The trouble with economics, though, is the assumption of the
  Rational Man at the center of it. When economics is utilized as
  a useful tool (talk about equivalent: UTILIZED... USEFUL ....
  TOOL .... that sentence fragment beats the point to death)....

  ...it can be helpful in decision-making. But answers requires
  not only a multitude of disciplines coming together, it
  ultimately requires going BEYOND any individual or combination
  of disciplines to get a "big picture"; which is, ultimately, a
  story that ties them together.

  Even THEN there's the application... and it's in the application
  that the rubber meets the road. Still, getting things perfected
  in models is very useful.