Continuity: When Stephen Dallas is first seen in his office, he's typing a letter. You can see that his fingers type several different keys, spaced out on the keyboard (probably in the middle of the middle rows), before he lowers his hands and stops typing to read. Then when he reads, you see that his letter ends with - -. It's not possible for him to have typed - - using the keys he was striking before he lowered his hands.
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