
Dan Butler is a talented comedian. Still, I've always puzzled about why he was brought in as a regular cast member. Frasier is a remarkably tightly structured show, despite the variety of its plots. Frasier, Niles, Martin, Daphne, Roz run the show quite effectively with assistance. The arcs don't require more major players.

I am not opposed to static characters! I'm not one of those culture lovers who demands that all characters be well-rounded. I don't get tetchy about "stereotypes" or "cliches" or whatever. All good comedy requires characters that grow and characters that remain exactly as designed. To a large extent, comedy relies on some flatness, even on cliches. We laugh at what we recognize.

Self-knowledge seems to be the key to transitioning from static or flat to well-rounded and dynamic. Bulldog is never given that. Larry Linville's Frank Burns might have been able to pull it off. The self-reflecting Winchester, however, arrived with self-knowledge already present (though not yet fully operational).
I guess if writers want a character to become dynamic, they should keep self-knowledge as an option, even if not fully displayed until later.