Is it a good idea to have some “hidden jokes” in your presentation that can be understood by only some persons that are part of your audience? In general the answer is no. It is not a good idea to have jokes in your audience that cannot be understood by your entire audience.
Think about what happens if the few persons in your audience get the joke and start laughing. The rest of your audience starts thinking if they missed something. The may actually start asking the
others what is so funny and you will lose the attention of your audience. Next you may need to explain the joke. Explaining the punchline of a joke normally does not make it not funny and
therefore doesn’t have a good effect.