There are actually more than four College Football head coaches who never played football. Some of them are Dennis Franchione, Charlie Weis, Paul Johnson, and Sonny Dykes. Also on the list are David Cutcliffe, Hugh Freeze, and Mike Leach.
Charlie Weis, Notre Dame head coach mike leach charlie weiss mike mangino paul johnson david cutcliffe george o'leary
bill belichick hasn't played in the nfl
charlie weis navy and 2 others in 08 09
There are 32 head coaches (one for every team) and a lot of assistants.
I believe it be very rare sinces you can't explain the game if you've never played it. You can't pass on or share pass experinces or give tip to become a better player. Then again there our coaches you have never played and I believe he or she is not benfitting their team or can't truly help them. That's just my little opinion.