With McCarthy's and Dak's experience and abilities that sounds absolutely logical.
Exactly, the only question is, to
@Haimerej 's point, is how much influence Mike has had so far. My guess, based on the move to sack Moore, was that Mike didn't have much say (presumably due to Jerry meddling) and wants control of the offense. I mean, if he had more say, then why sack Moore? So, to me, the decision to sack Kellen Moore suggests that Moore had more say into the offense, and now Mike will. If my guess is correct, then I think the experience that Mike has and the skillset that Dak has will be a nice fit. Bear in mind, a lot of your best (elite) quarterbacks are greatly aided by an experienced HC. Consider the likes of Peyton Manning and Tony Dungy, Tom Brady and Belichick, and even Patrick Mahomes and Andy Reid. Peyton Manning struggled before the arrival of Tony Dungy. Would Tom Brady have been as great as he was without Belichick (especially early on)? I think not. I think if he had, say, Jason Garrett coaching him early on, he'd have been considered as just another 6th round pick. He, of course, is a great QB. However, he needed Belichick early on, and Belichick needed him. As for Mahomes, yes, he's the best in the league ATM. But, what would happen if Reid wasn't his HC? Suppose Kingsbury followed him from Texas Tech to KC. Would the Chiefs be the juggernaut they are now with Andy Reid and Mahomes? I'd say these are examples of coaches and QBs being perfect fits for each other's systems.
I think the fact that McCarthy was able to create offenses for an old Brett Favre, a young Aaron Rodgers, and an aging Rodgers (before Rodgers became a petulant imp) and lead all three to NFCC games (and a Lombardi with Rodgers) at various points bodes well for Dak.