I am not so sure Martin has been used properly. When he only gets 5 to 8 carries a game and several of those are end runs what do you expect. He is big and can punish and wear down defensive lineman.He shold be given the ball 15 to 20 times a game and better than 3/4 of them should be between thy tackles.
He gets the ball once or twice and then the next 6 plays are passes. Not good to get a big running back in the groove.