Turns out, Dan Harmon wasn't the only person that Chevy Chase has issues with on the set of Community. According to Vulture, on a recent episode of Sklarbro Country, Director Jay Chandrasekhar described an instance during the filming of season two's "Mixology Certification" where Chase was rather unpleasant to him. This can also be described as Chevy Chase just being himself.
The bits are in three parts: beginning, and move along, and payoff. ... So I said, "All right, Chevy, it's time to shoot the second part of the bit," and he goes "eh, you don't need it." And I'm like, "Yeah, yeah we need it, we need it." He goes, "Nah, don't worry about it, you don't need it." And I'm like, "Yeah, well, we shot the intro, we shot the payoff, we kind of need the move-along section." He goes, "Oh, I see, are you telling me about comedy?" And I said, "Well, you know, in this case, I actually am." He goes, "Go fuck yourself!" And he gets up and he storms off.
Chandrasekhar goes on say, "I actually like and love Chevy Chase," and that the actor came back after ten minutes and shot the scene as requested. Oh, Chevy. Always keeping 'em on their toes!