Other mistake: When Michael borrows a cell phone on the train, he goes to the back to get a signal. In reality, walking around on a moving train does not do anything because you're already moving.
Character mistake: When Michael confronts Joanna in Chicago, he displays his NYPD shield as though he is about to arrest her, although he would have no jurisdiction there.
Character mistake: The conductors on Michael's train repeatedly call the seat check slips "zone stubs." Michael could make this mistake, but no conductor would.
Factual error: To derail the train, the bad guys shoot the operator, which causes the train to speed out of control. This is a well-known fallacy. All trains use a "dead-man switch" that will stop the train if the operator dies or loses consciousness.
Factual error: Michael boards a commuter train at Grand Central, which then stops at subway stations at 68th Street, 86th Street, and 110th Street along Lexington Avenue. This is impossible.
Answer: The opening credit scene (waking up, in the kitchen, the drive, being on the train, and walking through the terminal) is montage where each cut represents another day in Michael's life. It's meant to show the monotony of his life through the whole year (or even years) and how he follows the same routine everyday.
Bishop73