I do have a reason and will leave it up to you to decide if it is a good one or not.
At 5.03 minutes in this timeline special Roberts tells us Oswald entered the rooming house after 1 PM
If you believe her about seeing Oswald leaving zipping up a jacket, then why do you doubt her when she says this?
This is the reason I believe she was certain about Oswald wearing a zip-up jacket as he left the house.
Mrs. ROBERTS. He went to his room and he was in his shirt sleeves but I couldn't tell you whether it was a long-sleeved shirt or what color it was or nothing, and he got a jacket and put it on---
it was kind of a zipper jacket.Mrs. ROBERTS. Well, maybe I have, but I don't remember it. It seems like the one he put on was darker than that. Now, I won't be sure, because I really don't know, but is that a zipper jacket?
Mr. BALL. Yes---it has a zipper down the front.
Mrs. ROBERTS. Well, maybe it was.
Mr. BALL. It was a zippered jacket, was it?
Mrs. ROBERTS. Yes; it was a zipper jacket.
How come me to remember it, he was zipping it up as he went out the door.Mr. BALL. He was zipping it up as he went out the door?
Mrs. ROBERTS. Yes.
Mr. ROBERTS. Oh, maybe not over 3 or 4 minutes-just long enough, I guess, to go in there and get a jacket and put it on and
he went out zipping it."...All I remember-
he was zipping up a coat and I was trying to find out about President Kennedy..."
Mr. BALL. And when he was zipping up his jacket, his belt was covered?
Mrs. ROBERTS. Was it covered---well--- I don't know. I just couldn't answer you---I don't know---I don't remember it. I couldn't any more tell you than the man in the moon whether or not the man's belt was covered or uncovered.
All I know he was zipping his coat.Roberts is absolutely certain Oswald was zipping up a jacket as he left. She could not be any clearer. There is no room for doubt. Anyone questioning the certainty of this testimony on this specific aspect, cannot be taking the testimony as a whole seriously.
This is the reason I doubt the accuracy of Roberts' time estimate:
Mrs. ROBERTS. Now, it must have been around 1 o'clock, or maybe a little after,
because it was after President Kennedy had been shot-what time I wouldn't want to say because
The reason given for the time estimate is "because it was after President Kennedy was shot". This is simply not good enough. I cannot accept this as an accurate estimation of the time. She even states "what time I wouldn't want to say", indicating her vagueness about the time in question.
So I hoped for something a bit more solid in the video you posted:
"It must have been after one o'clock because...he come in, and you know how (unintelligible)...I tried to clear it up and he come in..."I have listened over and over again to the unintelligible part, maybe someone can help out. I can hear the word "blink" and that's about it. Judging from the phrase "I tried to clear it up", the best sense I can make so far of what Roberts is saying seems to be that it must be after one o'clock because she was trying to fix the TV!
There is nothing to verify Roberts time assessment so far. At the moment, it appears to me, she is just guessing.
In stark contrast to her testimony regarding Oswald's zip-up jacket.