To be honest, he's not progressing. Linehan is bringing him back a step with the playcalls from the Giants game. He had to because Dak didn't look ready to run the offense he had in place week one. The play design was good, but Dak failed to make the right reads or deliver the ball on time against Carolina. Yes, there were dumb penalties and the line did not always give him a clean pocket, but for the most part, they protected him okay. He ran into at least three sacks and did not hit the myriad of open receivers thoughout the game, who were playing against a fairly weak secondary (that got torched by Matt Ryan Week 2 for comparison).. While part of this was rust, due to the dumb decision by the coaching staff to not give him more snaps in preseason games, a lot of this was on Dak's development.
By bringing back the "spread'em out" RPO, as his base offense, Linehan is giving Dak a chance to be more effective now. It also might be a sign that Dak isn't ready to be an NFL Franchise QB too. He's got one more year to improve, but he should be farther along than he is. In this league, it is unusual for RPO QBs to a have long term success. Learning to be consistent from the pocket is the way a QB can have a lengthier career and desribes most Franchise QBs.