Oswald in the doorway: the blog of the Oswald Innocence Campaign, by Ralph Cinque

This is a quote from former policeman, Gil Jesus:

The Commission said that Baker " intended to continue around to his left toward the stairway going up but through the window in the door he caught a fleeting glimpse of a man walking in the vestibule toward the lunchroom.."
( Report chap. 4, pg. 151 )

But the only way Baker's line of sight would have allowed him to catch "a glimpse" of anyone "walking in the vestibule" was if that someone had entered the vestibule from the south, using the stairwell in the front of the building and going through either the office space or the corridor to the left of it.

So, according to Gil, Oswald had to have used the stairwell in the front of the building which was next to the doorway, just east of the doorway. 

And it makes perfect sense that if Oswald was standing in the doorway, which was in the southeast corner, that he would use the stairs that were right there in the southeast corner. But, if he had gone from the Domino room to the 2nd floor lunch room without going outside first, then he would have used the rear stairs. Look at the map. The Domino room was in back, and so was the second floor lunch room. So, why would he walk all the way to the front to take the front stairs only to have to traverse the same distance again on the second floor? Unless he was in the mood for some extra walking, he would not have done that. People instinctively take the shortest route from A to B. The only way it makes sense for him to have used the front stairs, as Gil determined that he did, is if he was in the front part of the building, that is, the doorway. 

So, even though there are some accounts that he "ate in the Domino room and then went up to the 2nd floor lunch room to get a Coke where he encountered the police officer..." those accounts are false, first, because there was too much time involved (time that had to be used up) and second, because if that was his course, he surely would have used the rear stairs. Look at the diagram again:

Bottom line: Oswald took those front stairs because he was standing in the doorway when he began his trek to the lunch room.