Revealing mistake: Jack did not rip Elizabeth's corset, as the sound effects suggest: the bustier's hooks were all already undone, and he just pulled the different pieces aside. (00:16:15)
Sereenie
Revealing mistake: When Elizabeth falls down from the cliff, with her hat and scarf falling over her, you can see it is definitely not Keira Knightley, as the stuntperson's face is perfectly visible. (00:15:05)