I am going to add as a p.s. to my previous piece that if you do the Math, it makes perfect sense that Oswald was in the doorway, and then left right about the time of the fatal head shot, and then took a little over a minute to get to the second floor lunch room slightly ahead of Marrion Baker. All Oswald had to do was go through the double doors, and then turn right to access stairs that were in the southeast corner of the building. He climbed the stairs to the second floor, and then he walked from there to the northwest corner of the building where the lunch room was.
The exact time it took is unknown. Marrion Baker was timed several times doing what he said he did, and the results fluctuated. According to Dr. David Drone, there was one take in which Baker did it in 70 seconds. But remember that he was running whereas Oswald just walked. And apparently he walked at a very relaxed pace because he was not out of breath when Baker saw him.
So, with Baker running and Oswald walking, and with Baker also losing time figuring out what to do about the stuck elevator before deciding to take the rear stairs, it's impossible to know exactly how their "race to the lunch room" played out. But, I do believe that if we assume that the Baker/Oswald encounter (where Baker saw Oswald passing through the vestibule room into the lunch room through the glass in the door) took place approximately a minute and a half after the last shot, we will be on pretty safe ground. And that coincides with the length of time it would have taken Oswald to make the trek starting from the doorway. Mrs. Robert Reed (her first name was Geraldean but, amazingly, she testified as Mrs. Robert Reed; talk about being old-fashioned) was standing right in front of the doorway, and it took her 2 minutes. She was timed at it too. Her desk was at the northwest corner, close to the lunch room.
Amazingly, this company was in the very simple business of buying text books wholesale from publishers and then selling them, supposedly to schools, although there is no evidence of any school-size orders, rather, only small orders. So, why would there be any need for a large clerical staff? If you've seen images of the 2nd floor, it's rows of desks. There was only one shipper, Troy West. How could he be shipping enough books to require oodles of clerical workers? We have never seen even one prepared parcel, a book order that was packaged, labeled, and stamped. We don't even know how they got labeled and stamped. Yet, there was enough revenue from Troy West's wrappings to generate income to pay all those salaries? 75 people worked for the TSBD, and that is a lot of salaries. How could one guy wrap small orders of books all day and generate enough profit to pay the salaries of 75 people, plus all the other expenses of the business? I'm telling you: the book distributing was just a front for the TSBD; they were really a CIA front company whose real business was espionage, hunting for Communists, and according to William Weston: gun running.
But, to return to our original topic, another thing that cements Oswald in the doorway is the high degree of correlation between his trek to the 2nd floor lunch room from the doorway, and Marrion Baker's trek there the way he did it. It really makes sense that they would meet up there at about the same time. Oswald started right with the fatal head shot, and we know that from Wiegman: the fact that they had to put that other phony Doorman in after Oswald left.
So, if Oswald left the steps at the time of the fatal head shot, and Baker reached the steps about 10 seconds later (giving Oswald a 10 second head start) it makes sense that they would get there about the same time since Baker was hustling and Oswald was not. The Math works. It adds up. And nothing else adds up. There is no basis to say that Oswald was anywhere else. He could not possibly have come down from the 6th floor because Oswald entered the lunch room from the office side, for which there was no access from the 6th floor. Oswald did not use the rear stairs to get there. He used the front stairs. These stairs:
And this is the route that he took:
So, you see the icon for the stairs on the lower right. Those are the stairs Oswald used. And then he could have either walked the hypotenuse of the triangle, as I have indicated, or walked the base and altitude of the triangle, but I assume he walked through the office area for two reasons: 1) because the shortest distance between two points is a straight line and Oswald knew that, and 2) he walked through the office area upon leaving the lunch room, which is how he crossed paths with Mrs. Reed.
All of this makes sense. All of it works. And there is no alternative to any of it. This is what happened.