Linehan is actually using Dak correctly. He isn’t being ‘mid-used’. It’s pretty clear they want him to manage the game and not turn the ball over, while relying on the running game. They want him to make plays when he needs to. This is similar to what they tried in 2015 when Romo went down, while the defense continued to hold the opposition out of the end-zone, which they actually did in 2015.
The problem with this conservative approach is, he’s too inconsistent. You can substitute Dak with any game manager and get yet same results, if not better especially the way Zeke is running, particularly if you got a guy who throws in the middle of the field or somewhat accurately deep.