It should first be noted that William Hoffman was a Physics Graduate student in the 1960’s. Perfectly competent to make estimates of movement from the Zapruder film. Making accurate estimates is just what a Physics Graduate student is supposed to be good at, and would have a lot of experience at this. He was hired by Josiah Thompson for this work because he had the skills, to make the measurements that he hoped would prove a frontal shooter, and publish this data in his upcoming book “Six Seconds in Dallas”. And Mr. Hoffman would almost certainly have been unaware of the neuromuscular spasm hypothesis so he would not have been consciously or unconsciously adjusting his measurements to match it. It would impossible to find such an expert today that one was confident that he had not heard of this hypothesis and did not already have an opinion, one way or the other.
On the question of whether the neuromuscular spasm occurred, or not, my layman opinion is:
The Zapruder film shows it did.
As has been pointed out many times to you, Kennedy's reaction/movement is unlike anything we see in the goat's neurospasm reaction. So how on earth can you claim the Zapruder film "shows" JFK's backward movement was caused by neuromuscular reaction, especially given the fact that science tells us that human neurospasms involving similar movement cannot occur sooner than 100 milliseconds after stimulus?
Just because you want and need the neurospasm theory to be true does not remove the scientific and readily observable objections to the theory.
There is no other explanation for what it shows.
"No other explanation"
Really? The HSCA FPP gave the jet-effect theory as its first explanation for JFK's movement, followed by the neurospasm theory, and then, to cover all bases, said both phenomena might have been involved. The FPP simply ignored the problem that there is no evidence that a human neurospasm involving the movement of that much weight could occur in 40 milliseconds.
And of course there are other explanations for JFK's movement, but your version of the assassination won't allow you to accept them. If the bullet that struck Connally in the back could push his right shoulder down and forward, a bullet could have caused JFK's head to move backward, as a long list of physicists have observed. Dr. James Riddle, who was a physicist at UCLA:
The motion of Kennedy’s body in frames 312-313 is totally inconsistent with the impact of a bullet from above and behind. Thus, the only reasonable conclusion consistent with the laws of physics is that the bullet was fired from a position forward and to the right of the President.
In the 1990s, I interviewed several aeronautical engineers about the jet-effect theory. They all thought it was laughable. And, of course, Dr. Chambers has demolished the jet-effect theory. Dr. Chambers has also established that the backward movement is consistent with a shot from the front, and Dr. Mantik, a highly qualified physicist in his own right, agrees that Dr. Chambers has showed this:
G. Paul Chambers has shown that JFK’s head snap is fully consistent with a frontal shot. (https://themantikview.com/pdf/Omissions_and_Miscalculations_of_Nicholas_Nalli.pdf)
Then, if we factor in the mountain of evidence that the Zapruder film has been altered, we can logically postulate that JFK's head movement was altered to remove visual indications of two bullet strikes--one moving his head forward and the other moving his head backward but to a lesser degree/less dramatically than we now see in the film.
1.The Head moves forward from z312-z313.
Consistent with a bullet strike from behind. This can clearly be seen in the Zapruder film.
It is impossible to tell if the head moved with constant momentum, because this movement
does not last over one frame interval, but there is no reason to assume it didn’t, all followed
the laws of conservation of momentum.
Not only is this what my layman eye shows me, but is what the careful measurements of
Physics graduate student William Hoffman show.
2. The Head starts moving back in the z313-z314.
This shows the backwards movement started 40 to 80 milliseconds after the bullet impact. Consistent with the 1948 U. S. Army film of the goat, which Larry Sturdivant testified started moving after 40 milliseconds.
The careful measurements of Physics graduate student William Hoffman show the head started moving backwards one frame later.
3. The Head moves backwards from z313-z315, with ever increasing speed.
This is not consistent with movement caused by a “push” from a bullet from the front,
which should deposit all its momentum while within the head, within a one to two milliseconds,
after which the head should move with constant momentum, not continuously pick up speed.
Not only is this what my layman eye shows me, but is what the careful measurements of
Physics graduate student William Hoffman show.
4. From z315-z318, President Kennedy’s right arm starts to move up.
During this interval it moved up 6 inches at the elbow. It moved up 3 inches from z315-316. This movement
Is consistent with a sudden speed upward of 3 mph was imparted to the right arm, and then was solely
Under the influence of gravity, which should cause it to reach its apex during z318-z319, then fall down.
This is exactly what the Zapruder film shows me. The Head moving back early, followed by the right arm,
Is exactly what one would expect if the neuromuscular spasm hypothesis is true. The view of his left arm is
blocked, so we cannot tell if it moved upwards as well, or was perhaps held down by Mrs. Kennedy, assisted
by the weaker pair of muscles in President Kennedy which would try to pull the arm down.
William Hoffman did not comment on this movement, but it is clear for anyone to see in the
Zapruder film.
Right, so I guess you just don't care that Dr. Art Snyder, a physicist at the Stanford University Linear Accelerator Center, proved to Thompson's satisfaction that Hoffman's measurements were wrong? Does it matter to you that Dr. Snyder rejects the jet-effect theory for JFK's movement (1) based on the laws of physics and (2) based on his own experiments?
Clearly, if one is guided by what one sees in the Zapruder film, the muscles of the President were activated as a result of being shot in the head and are totally consistent with the Zapruder film
Whaaaat?! Again, do you have a copy of the Zapruder film that no one else has seen? What in the world are you talking about? Nothing like what you describe is seen in the Zapruder film that the rest of humanity has seen. In the rest of humanity's copy of the film, JFK's limbs don't splay, and his head moves before his shoulders move. As Henry Hurt noted,
A motion picture was shown of a goat being shot in the head, causing all the goat's muscles to go into a violent, involuntary spasm. Clearly, this does not appear to be what happened to Kennedy, whose whole body appears to go limp as he is thrown backward. There is no splaying of his limbs, as in the shooting of the goat. (Reasonable Doubt, p. 130)
How can anyone reason with you when you keep pretending to see things that simply are not there?
, and not consistent with “simply physics” and “pushes” from bullets, unless there were a stream of bullets striking him in the head, one bullet per frame during z313-z318, plus another bullet from below striking the right elbow.
Yeah, uh-huh. Newton just got it wrong, huh? The bullet that struck Connally visibly pushed his right shoulder down, but the bullet that hit Kennedy's head from behind--abracadabra--pulled it backward! I guess you've already forgotten about the fact, which I personally pointed out to you, that Alvarez falsified his test data because the melons he shot kept being propelled in the same direction that the bullets were moving? (Gosh, who would have thunk it?) Remember that? You might also want to read Dr. Chambers' chapter on the backward head movement.
No one knows is that injury would prevent the neuromuscular spasm. My layman’s eye shows the elbows held very high immediately after z222, but gradually coming down by z312, showing the effects of this bullet was fading away within a few seconds, as sometimes happens after trauma to the spinal cord. Temporary paralysis is common in American football, which goes away in a minute or two, or longer.
The spinal cord was not severed. Tiny chips were dislodged from near the end of a thin fin of bone of one vertebra, but not severed. I don’t think Mr. Sturdivant claimed the President grasped at his throat. I’m sure he would go with Dr. Lattimer’s opinion, that President Kennedy was in the Thorburn position, immediately after the shot at z222. In my layman’s eye, this position was going away by z312, as trauma caused to the spinal cord can be temporary in some cases.
There is no way Dr. Thomas or anyone else can know this. It is impossible to say how much the spinal cord was damaged. It would be impossible to wound an animal, with the same amount of damage the President had at z222, because no one knows how much damage was caused, then see if the neuromuscular spasm occurs five seconds later with a shot through the brain. Dr Thomas is simply making unwarranted assumptions.
Oh. Come. On. You must be kidding. So the FRACTURE of the spine at T1, which is just below the base of the neck, would not have at least substantially hindered, if not prevented, a neuromuscular reaction involving the head and shoulders 5 seconds later??? Really??? Let's read the HSCA FPP's description of the damage again:
. . . the X-rays indicate that the missile track proceeds toward the midline of the body. This analysis is based on the fracture of the transverse process of T-1. . . . (7 HSCA 93)
(440) The panel agrees that the tissue disruption due to the temporary cavity created by passage of a high or intermediate velocity missile might have produced fractures of the transverse processes of one or several of the lower cervical and/or upper thoracic vertebrae in President Kennedy's neck, as indicated by the postmortem X-rays. There are significant muscle masses attached to the vertebrae which would receive tremendous shock, even if several inches distant from such a missile. A direct grazing missile impact may have occurred, but it would not have been necessary to cause the damage visible in the X-rays. (7 HSCA 171)
IOW, the shock received from the shock wave caused by the bullet's impact and penetration could have fractured T1 even if it didn't hit, and the "significant muscles" attached to the vertebrae in that region received a "tremendous shock" even if several inches from the missile itself.
And you're telling me with a straight fact that the spinal cord suffered little or no damage from all this?
Dr. Thomas is not making any "unwarranted assumptions." He is basing his observation on the damage to the spine that the HSCA FPP identified and described and on the medical scientific fact that neuromuscular reactions require a functioning spinal cord. A spinal cord in a spine that has just suffered a FRACTURE at T1, as well as the other damage to the area described by the FPP, is not going to be capable of producing a violent neurospasm that throws the head and shoulders backward, especially not in the impossible timeframe of 40 milliseconds after bullet impact.
We both know that the real problem is that your theory of the assassination requires you to peddle these “bizarre and implausible” theories, as Dr. Chambers has called them.
Dr. Lattimer had superior training, and superior experience treating wounded soldiers, then either Dr. Zacharko or Dr. Thomas, on dealing with the question of the neuromuscular spasm hypothesis.
LOL! You’re citing Lattimer as your authority on this?! Oh. My. Goodness. Yeah, okay. Whatever you say. This is clown material.