Okay. wow. I found some foreshadowing about the ending in one of the early episodes
When Michael is getting Andy Richter to jump on board for his movie there is this:
Andy: So they're finally making a movie about that, huh?
Michael: Theres more to it than that...Its about a young man trying to get out from under his domineering Father, while dealing with the slow death of his wife.
Obviously later we learn the movie was supposed to be about Michael and GM, not Michael and George...which is
exactly what this
entire season up to that ending leads up to (metaphorically).