The funniest racism is the racism between minorities. It's something you don't see dramatized, but almost every minority I know who's my age, they have these funny stories about their parents stereotyping other minorities.
When actors are the real deal, all that star whatever goes right out the window and you're there to tell a story.
You can time a part perfectly and play it badly. And some people have very individual offbeat timing, which is their own. It works simply because they are who they are.