The Same Jokes used in different episodes. Repeat jokes?

[Radioman]

Or are they west coast episodes?

As I make my way through the Jack Benny program in the early 1940s, I jump around a lot, and notice repeated jokes used. I know that some of these might be the west coast broadcast, so the same joke is told, but sometimes a different punchline is added.

But sometimes I get dejavu thinking that I know I've heard this gag before, or an entire scene, but the whole setup is different. How often did they do this?

One gag that comes to mind is one where Rochester is driving Jack someplace and Jack tells him to park the car. Rochester asks why not use a parking garage? And Jack simply says, "Rochester!" And Rochester says something like, "Sorry boss, I forgot." This gag, with Jack simply saying "Rochester" is hilarious all by itself.

But I heard another version of this same scene in an episode I've forgotten, where Rochester asks about parking in a garage, but Jack's rebuff line is longer, and so is Rochester's follow-up. This version wasn't as funny as the previous.

I've noticed this sort of thing several times so far. Is it really happening, or am I hearing things?