OK, so in "Creature From the Black Lagoon" the film historian's commentary claims that "Creature" was the first film to do the "...I'm so scared. Eeek! Something touched me, oh wait, it's my friend tapping my shoulder." gag.
So lets see if we can identify the first documented appearance of other total cliches.
Here's one:
- I person is delivering a speech that they don't want to. We cut, and see that they are along, practicing it. Ha ha.