I am not comparing Murray to Peterson, don't be ridiculous. I am contrasting the two teams who played Sunday in the most recent contest for the Dallas Cowboys. Murray looked very good early on, when he was getting touches. He had bounce in his step, was cutting hard and had good burst. He was finding holes and making defenders miss. I have watched the game several times. There was nothing in this particular game to indicate we would have had a real difficult time running. It certainly wasn't evident on the few carries Murray did get.
Simply put, it is impossible to gauge what this team can do running the ball, because we don't ever run the ball. What you say are simply excuses. Callahan has never run the ball, even with a beefy oline in Oakland and some very very good talent in Nebraska. Garrett showed absolutely no commitment to the run when he was offensive coordinator, before and after becoming head coach, with all different levels of talent.
Tony Romo had 17 incompletions. Do those incompletions not result in 2nd or 3rd and long? Did they not have anything to do with the sacks that hurts drives several times? Murray averaged 7.8 yards a carry. Romo averaged 6 yards a pass attempt.
Don't try to convince me this is a down and distance argument when time, fact and logic make it clear this is a philosophical issue. Callahan and Garrett don't believe in running the ball.
And, if you want to make this an argument about protecting the defense, runs (even for no gain) take significantly more time off the clock than incompletions, penalties and sacks.