I really appreciate the posts here.  The link to "adjusted days lost" was indeed useful as much as anything through its  identification of many of the factors that can go into the impact of injuries to the game.   It is obvious that loss of a star player on a team with poor depth can mean more than the loss of a player who is just marginally better then his backups.  Usually when a team says that its positions are very competitive, it means that loss of one player will not be as consequential as when they are not.  The long season makes injury luck very important for team success.  Maybe this bodes well for this years Jaguar team.  

 

And, of course, the special requirements for good quarterback play also can make a loss at this position of greater impact than the loss of a single lineman for example.

  Thanks everyone. 

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