The Jerk is more inline with the type of humor that Steve Martin did as a stand up comic. He doesn't use any of his jokes in the movie, that I am aware of. As far as I know he didn't pull material from his stand up comic days and put it in a movie. It is just similar humor. If you ever saw a video of Steve Martin doing stand up then you might have an idea of the type of humor to expect.
I thought Martin was hilarious as a stand up comic but my oldest brother could not stand him. I also thought Robin Williams was hilarious as a stand up comic when I first saw him (on TV, I haven't actually been to their stand up shows). After awhile I did grow tired of Williams stand up type of comedy. However, both made some really outstanding movies and both have even done well in non-comedy roles.
Anyway, I really liked The Jerk. I also liked his Dead Men Don't Wear Plaid movie as well but then I'm I guess I'm easily amused.
When I lived in the LA area my wife and I went to see a play that Steve Martin wrote called Pablo Picasso at the Lapin Agile. I believe that was the funniest thing that Steve Martin has ever done. He wasn't in the play, he just wrote it. It is the imaginary meeting of Pablo Picasso and Albert Einstein and it all about which is more important to mankind, art or science. And then Elvis shows up at the end.