Original Commentary
When you get down to it, that's the difference between those two: Kimberly is a pessimist and Brisbane is an optimist with bad luck and a bruised apple.

Modern Commentary
Optimism vs pessimism, right there. That's why they work so well together. Brisbane's day was, on paper, worse in ever way but he's got a positive attitude to see him through.

Yes, they mention each others' names often. It's a thing we do.
Reason for that is that every strip is somebody's first. Every strip has someone coming back who hasn't read the comic in a little while. Every strip has someone reading it who's reading a few dozen other comics and maybe isn't fully concentrating on our little comic here.
There are times I'm reading someone else's comic and I think I recognize a character but I'm not sure who they are or what their deal is. And I scroll to the archive and their name hasn't been mentioned in months and the characters page hasn't been updated since the comic launched.
So I try not to do that. The characters call each other by name often.- Terrence