My estimation of what happened, at the TDL, Adams didn't want to commit to Mitts (because of the timeline he had at the time) just as you said. And he probably felt good about that decision as he felt he had time to mature Krebs into the Mittelstadt role (3C), so he felt comfortable making that decision, as he made mention at the time of the TDL of putting more responsibility onto Krebs.
But then I think Terry and Adams talked closer to the end of the year, one of the important games between post-TDL and end of the season, where the leash got extremely tight and Adams seat had a massive increase of heat applied to it. Hence, why the presser of Granato's firing was a completely different tone and had a different sense of urgency to it.
I think if Adams of the TDL had the knowledge that today's Adams had, I think he commits to Mittelstadt and doesn't trade him. I think at the TDL, he most likely thought he had more time, and so he made a hockey trade to get something for Mittelstadt.