I agree with burroball, a head coach at a high school is a job within itself. So many behind the scene responsibilities for a HC, which are not recognized. There are many issues that will not have to be address in the same magnitude, as in a metro school. It should be an easier ride for an experience coach. A guy with NFL experience, an ambition to coach, decent people/coach skills, and an understanding of the demands of HC, possess many tools of being a great coach. Based on his short High school experience, He has somewhat of an understanding of the demands.
Whether he deserves it over an more experience successful area coach is another thing. With Law, only having the responsibilities of running the O could be a good thing! Dyson only put the blunt of the responsibilities on himself, and let the more experience coach run his O.