Hypothetical question

[John Corbett]

The initial movement of JFK's head, as a result of the headshot, is forward and down (as seen in the slowed-down GIF below). The illusion is that this movement is so quick it can't be detected by the human eye and we are left with the so-called "back and to the left" movement (which is simply JFK's head rebounding off his chest as a result of the explosive force of the headshot):



As for the topic of this thread, I believe interest in this case would have fizzled out in the '70's if it wasn't for the Z-film being shown on Geraldo. The Z-film reignited interest in this case and has been the driving force of this interest for so many decades.

I think there would be less interest in the assassination without the Z-film and probably no HSCA. But the WC skeptics were out in force before the Z-film was made public so I'm not sure WC skepticism would have died out completely. CT bibles Six Seconds in Dallas and Rush to Judgement had already been published and Ruby's killing of Oswald fueled much of the early belief in a conspiracy. Would the skepticism have continued into the 1980s and beyond. Probably, but not on the scale it did. I don't think Oliver Stone would have bothered making a movie about the JFKA.

[Andrew Mason]

Without the Z-film, how would Frazier know JBC was turned too far to the right. There would have been no Z210 and no Z240.

The Z-film was the timepiece for the JFKA. Without it, the WC would have nothing to base the timing of the assassination on the sequence of the shots.

That was my point:  “So it does appear that the zfilm was important in creating the SBT.”

They probably would have figured out the headshot was the final shot but would have nothing but conflicting eyewitness accounts on which to base much else. More unknowns would have given the CTs more opportunities to fill in the blanks.

They would not have had conflicting witness accounts on the first shot causing JFK to immediately react. That’s why I suggested that if the SBT had been considered (because JFK did not stop the neck bullet) it likely would have been a first shot SBT. 

[Jarrett Smith]

I could be wrong, but I don’t think there is any other photographic evidence that seems to clearly show a “back and to the left” JFK head movement. So, perhaps we might have avoided that controversy.

The Nix and Muchmore films show back motion from the head shot, so more people may believe in a frontal shot.

I think the SBT survives, but many of the witnesses heard 3 shots with the first being at Z-223 when both men react. Connally heard a rifle shot before they were both hit that many others missed. I suppose without Zapruder's film they would rely on Croft, Willis, and Altgens.