Dan Harmon did a really good AMA yesterday: http://www.reddit.com/r/IAmA/comments/y ... writer_of/
This exchange in particular is great:
some dude wrote:
The rumour mill says that Chevy Chase walked off set at the end of filming for Season 3 because he refused to do something. What did he refuse to do?
Dan Harmon wrote:
He refused to do the "tag" for the Digital Estate Planning episode (the 8 bit video game episode). In the scripted tag, Abed comes to Pierce with the thumb drive he took, and says "Pierce, I've been able to adjust some of the code for your Dad's video game and I've made a version I think you might like better." He puts the thumb drive into a laptop in front of Pierce. We cut to the laptop screen, where we see Pierce's avatar on a front lawn with the giant floating head of Cornelius. Every time Pierce presses the space bar, his avatar throws a baseball to his father's head, which gives him a thousand points and a "great job, son!" Pierce presses the space bar a few times, pauses, then leans over and embraces Abed and we fade to black. When Adam Countee pitched that tag, tears instantly rolled down my cheeks, and in point of fact, my eyes are getting watery describing it to you. It was the most important part of the episode and possibly one of the most important moments of the season. I was very upset to hear that it wasn't shot because someone didn't feel like shooting it, especially since it was literally the last day of shooting, which meant we'd never be able to pick it up. I regret nothing about how upset I got. My job was to care about my show.
another dude wrote:
Why did he refuse to do it?
Dan Harmon wrote:
The answer I heard from the people on set was that he didn't think it was funny. After he realized how upset I was about it, he said things in voicemails like "there was no script" (untrue) and "I have a weird relationship with the name Cornelius" (dumb, he had no dialogue in the tag). The real answer, I believe, is that he wanted to go home because he was tired. He probably didn't realize he was permanently damaging the episode by doing so because he often walked off set and then we would just pick up his shots later in the week. But this was the final shot of the season. The sets came down after he walked away. So this was the one time in three years that his personality caused unfixable damage to something I really held valuable.