That the Cards interviewed Bettcher for the HC position is a message to whoever gets the job that they think highly of him. If the new guy is an Offensive specialist, I want him worrying about that side of the ball in 2018.
My thoughts too. Bettcher isn't a huge ego guy like Ray Horton was. He should know that he won't become a HC anytime soon, and probably not even land a DC somewhere else right now. Overall, Bettcher did a good job with a young unit and got better as the season went on. We for sure will start over on offense, so having continuity on defense would be a plus if the new HC is offensive-minded with no clear DC candidate in petto. If this business relationship between offensive HC and DC Bettcher works, then great for everyone. If our defense struggles, we can fire Bettcher and start over on defense. I'm saying this and I'm not even a huge fan of Bettcher. Just think our defense is headed in the right direction and rebuilding offense + defense would be too much.