This slip-up happened in the commercial for the Partidge family movie, so it may be intentional, but here goes: When The guy who plays David Cassidy is caught by the guy playing Danny Bonaduce making out with a girl, Danny calls him, "Keith", his character in the show. Yet, by the look of the scene, it looks like this happened in real life, not in the TV show, so wouldn't Danny call him "David", his real name? I doubt they would have an episode of "The Partridge family" where Keith is caught making out with a girl.