DJ McCarthey and Mark Farrell confirm what Jacob Weinstein was saying: in writing comedy you need to leave a gap between how the line reads on the page and how it will sound. If you write the way the character sounds, it'll be overkill. You need to leave room for the performance. Brent Butt underwrites his lines so that when he says them, he can add the drollery by his performance.
The ironic thing there is that as Mark pointed out and DJ confirms, you can get an audience laughing with poor materal. Not necessarily bust-a-gut laughing, but enough to sustain a working career as a comic. If your performance is where it should be, the material can fall way short. Sheer skill with an audience can cover up a big nothing of a written act.
The other thing that came up in my conversations with Mark and DJ is Mark's description of comedy as "plausible surprise." The essence of a joke is that you set up a situation in which you lead the audience by the nose in one direction, and then pull the rug out from under them. You need to know where they expect to go, and then not go there.
More on my conversations in comedy soon...