Yet again I have to waste my time correcting your incompetence.

JBC stated that he tried to look over his right shoulder after hearing the first shot, to check if JFK was OK.
It is Corbett's assertion that the Z-film shows JBC attempting to look OVER HIS RIGHT SHOULDER, just as he testified to doing.
It's my assertion that at no point before JBC is shot at z222/z223 does he make an attempt to look over his right shoulder to check on JFK.

Let's see who is being honest about this.

JBC is looking to his left around z163 (Corbett likes to say "hard" to his left or "hard" to his right, in a truly desperate attempt to equate what we actually see in the Z-film with what he would like us to see. It's enough to say he is just looking to his left).
JBC quickly turns his head to the right, presumably in response to some kind of stimulus, and by z169 he is looking to his right, in the direction of the crowds lining Elm Street:



Obviously, it is Corbett's contention that the stimulus JBC is responding to is the sound of a shot and we are seeing JBC in the process of turning to look OVER HIS RIGHT SHOULDER. In fact, the stimulus is very well documented and I will get to it in a bit.
Strangely, if we are to accept Corbett's falsehoods, JBC reacts quickly by turning to look to the right, but then he stops moving any further to the right. But he's supposed to be worried about whether JFK has been shot or not. He's supposed to be trying to look over his right shoulder (JFK is smiling and starts waving btw, so he's OK).

But by z193 his head is in exactly the position it was in z169. He is still looking towards the crowds lining Elm Street as he passes behind the Stemmons sign:



Why has he stopped turning his head if he is desperately trying to check on JFK?

Surely, if Corbett is to be believed, JBC should be straining around to look over his right shoulder as he travels behind the Stemmons sign. By the time he emerges from behind the Stemmons sign he should be looking over his right shoulder.
But that's not what we see in the Z-film.

What we actually see is that JBC is in exactly the same position he was as he passed behind the Stemmons sign. He is still looking towards the crowds lining Elm Street:



As usual, Corbett is talking nonsense.
The Z-film does NOT show JBC trying to look over his right shoulder at all.
It merely shows him looking in the direction of the crowds lining Elm Street to his right.
There is no disputing this (by rational people, that is)

This is from an article in the Dallas Morning News entitled, "Witness From the News Describes Assassination", written by Mary Woodward the day after the assassination [lifted from Pat Speer's website]:

"Four of us from Women’s News, Maggie Brown, Aurelia Alonzo, my roommate Ann Donaldson, and myself had decided to spend our lunch hour by going to see the President. We took our lunch along – some crackers and apples – and started walking down Houston Street. We decided to cross Elm and wait there on the grassy slope just east of the Triple Underpass, since there weren’t very many people there and we could get a better view. We had been waiting about half an hour when the first motorcycle escorts came by, followed shortly by the President’s car. The President was looking straight ahead and we were afraid we would not get to see his face. But we started clapping and cheering and both he and Mrs. Kennedy turned, and smiled and waved, directly at us, it seemed. Jackie was wearing a beautiful pink suit with beret to match. Two of us, who had seen the President last during the final weeks of the 1960 campaign, remarked almost simultaneously how relaxed and robust he looked. As it turned out, we were almost certainly the last faces he noticed in the crowd. After acknowledging our cheers, he faced forward again and suddenly there was a horrible, ear-shattering noise coming from behind us and a little to the right.

When we examine the Zapruder film there is only one moment when both JFK and Jackie (and JBC and Nellie) are looking toward the crowds lining Elm Street to their right and it is when they both begin to turn around z170. This is the moment Woodward is describing when she states "both he [JFK] and Mrs. Kennedy turned, and smiled and waved, directly at us..."
I have cobbled together a couple of Z-frames to illustrate this moment. I've used z152, which shows Woodward's position and overlaid z170, the moment when Jackie and JFK begin to turn to their right:



The moment when Woodward and friends call out, making all four occupants of the limo turn to their right, is recalled by Vickie Adams in her WC testimony. Adams is watching the motorcade from the fourth floor and states:

"I watched the motorcade come down Main, as it turned from Main onto Houston, and watched it proceed around the corner on Elm, and apparently somebody in the crowd called to the late President, because he and his wife both turned abruptly and faced the building, so we had a very good view of both of them."

Both Adams and Woodward insist the first shot occurred shortly after this moment, ruling out an earlier shot.
JBC is NOT turning to look over his right shoulder because there has been no shot up to that point.
The first shot occurs at z222/z223, just after JFK has finished smiling and waving at Woodward and Co.

Oh, really, Matt ?  As “rough” as a B & E to get a film ? lol, you’re a riot !

Never did touch the (Dis)education Forum but dang, it's gotten to that point? Guess that "forum" is rough.

Trump [has] been unfairly accused on some points.