I used to think Bruce was the least funny, but now I think he's the best. Dave is totally funny, you guys. He just happens to be the most conventionally charming/funny and had the most "cross-over" appeal and Petey has an obvious case of normalphobia. The heavy-leg thing is the worst thing Dave ever did. Who's the worst? Without a doubt, it's gotta be Mark. Not only did he do that "I'm a Cat" sketch, which is like the animal version of Billy Crystal's Blues Man. Not to mention his blues man character, which is the Mark McKinney version of Billy Crystal's Blues Man. Not only is he the least funny, he's also creepy. His performance in Brain Candy is transcendant and awesome, but pound for pound he's the worst.
1. Bruce
2. Kevin
3. Dave
4. Scott
5. Mark
...or KicktheBobo's list works fine too.