Originally Posted by RedsManRick
Have any other shows seen turnover at the lead this deep in to the series and then gone on to put up quality years afterwards?
The thing is, he's not "the lead," because it's an ensemble cast. That's why ER is such a great parallel for the way this could go, IMO.
ER survived just fine without Clooney, Edwards, Margulies, etc. Just like The Office could survive without Michael, Jim and Pam.
By the end of ER, none of the leads who started with the show were still there. Since both shows center on a workplace, rather than the home lives of the characters, it makes perfect sense that people would move on from that workplace, just as they do IRL.