I think you are on target when it comes to the mental part. Mac Jones is incredibly smart. So much so he was named Academic All American of The Year. You’ve already heard stories about his picking up the offense and learning it extremely fast, one of the toughest offenses to learn. I definitely think that’s ONE of the reasons why Belichick is going with him. If the rumors are true he was helping Cam with the playbook (I highly doubt that rumor), that would be insane. His intelligence is off the charts.
But I also think he has a Brady-like chip on his shoulder. Lightly recruited, lightly regarded, had to wait his turn, ala Brady. He has the heart and determination to be great and to win. What he and Alabama did last year impressed me more than any recent FBS Championship team. 13 games against the toughest conference in football, 13-0. Like we saw in the Brady 6 documentary, Coach Mariucci said about Brady, we didn’t measure his heart. We don’t know about Jones’ heart yet. The games will tell.
Now could be bust ? Sure, we see it all the time. Also, he will make mistakes and some may be ugly, but that’s to be expected from a rookie. Even Brady threw 12 INTs his first year starting, and I read he fumbled 12 times his first 3 years. Mistakes will be made, even Belichick mentioned that.
But he has certain qualities that I think will make him bust proof. His intelligence, quick release, ability to read defenses and his accuracy. I haven’t seen any difference from college to pros yet. 69% completion percentage with 9 drops, would have put him near 72%. His accuracy is so impressive.