Hey, I'm a Sooners fan. I'm aware of their history and Murray's. I just don't think he's a special running back. He's very versatile. He's a complete back. But he's not special. If this was 20 years ago, sure. Resign him. In today's NFL, I don't see the value in it.
The Cowboys hit walk off grand slam home runs with three 1st round picks along the line. The luxury in that is it should allow you a wide range of running backs capable of performing behind that line. I don't think you maximize that benefit by paying big long term dollars to a veteran with durability issues.
Extend Travis Frederick. Begin the framework on Zack Martin's next contract. Don't overreact to the RB benefitting from their play. The league is filled with backs capable of doing the same with this offensive line and the way they're playing right now.
The salary cap forces you into these kinds of decisions. You have to be very selective on who gets a big 2nd contract. Is that player replaceable? How easily? With DeMarco, I think those answers are yes and easier than losing one of those offensive linemen down the road.