Garrett coached his last year without an extension. If fatso gets one, it'll be one year at most.
This is where the real penny pinching comes in with Jerry. There is no salary cap on head coaches. You could give the guy a 5 year extension and make him look like a made man. You can then pick almost any assistant you want. And next year cut his ass. You have the money to do it. And there is no salary cap implications.
But ole Jerry hates paying coaches. So the thought of giving a guy a five year deal and not having him coach the full 5 years just kills him. So he won't do it. Because he is pinching pennies. He also won't pay top dollar for a coach. Because he is a cheap ass. So the thought of him going out and getting a Vrabel, or Bill or whoever. It's not going to happen unless those guys want to take less money to have an owner who will try to walk over over them.
Again, when it comes down to it, Jerry is a cheap ass. He will play it off like he is willing to throw any money at this thing to win a superbowl. But he won't. He uses the salary cap as an excuse to not have to throw that kind of money at players. He won't do it with coaches. The whole concept that Jerry will spend whatever it takes to win a Superbowl is just an invention of Jerry Jones to market to fans.