Following that argument then simple-minded businessmen or people with a Manichean world-view should be great at taking care of babies, since they make quick judgement calls?

It sounds a little too simplistic, doesn't it?

That's a function of how well calibrated are those judgement calls with well-being of the baby.

Soldiers who make quick judgement calls are better than ones who don't; but they're trained to have their judgement properly calibrated with the task at hand.