for moments like those don't comics and shows just use the convenient interruption? like in the simpsons someone'll say "welcome to springfield, part of the great state of-" "HEY! IS THAT A PIG PLAYING A PIANO!?" or in comics someone's about to drop a big secret but it's covered up by another characters speech bubble. or hell like in mlp, pinkie and the apple family, big mac is about to talk about what he learned and granny smith just cuts him off before he can say anything. like a running gag where the audience keeps expecting it to happen but it never does due to a series of random events.