The Carol Burnett show was generally well-written and acted, but the “Tim Conway is soooooo funny, I can’t keep a straight face” schtick from Harvey Korman was tiresome — and obviously fake after the first time, and maybe not even then. But the audience came to “expect” it, and the actors & script writers delivered.
Pretty sure they did two shows a night...one as straight as possible, and another where the actors had more leeway to ad lib.