You can hear the answers to why Theo left in between the statements he made.
He could not give it his heart and soul anymore? That's Lucchino, Steinberg, et al., behind that statement. The fact is, he did give it his heart and soul, and succeeded, and for that he expected more respect than he got, not in terms of money, but in terms of how the entire thing was played out in the press - and nothing in the press came from him, on that everyone agrees. He kept his part of the bargain (no agent, no public statements or negotiations). It was the "adults" who could not keep to the deal.
Shaughnessy tried to slip and slide and deny and accuse his way out of it yesterday on WEEI and all I could hear was, "I did not have sex with that woman" and "I am not a criminal." He and Lucchino are too close; Shaughnessy may not have spoken to Lucchino after the joint call with Theo (which he claimed yesterday on the radio) but he knew what he had to do: put that young pup in his place on the eve of his new contract to remind him who was really in charge here.
This is classic Shaughnessy, always looking for an opening in which to inject himself and then hide behind, "I just write my opinion." If there ever were a more small-minded, self-important, backstabbing columnist in the sports press than Dan Shaughnessy, he would have to have been a presidential press secretary in his previous life - or perhaps a prison snitch.