Let's take another look at the Penn and Teller Demo. After the magician, Penn tells us what we are going to see, what actually happens? There are two heads, the first head simply explodes, most of the debris exploding in the direction of the shot. Now you could argue, like Penn, that this proves a natural head snap in the direction of the shot, but does it? One could also argue that that first head explosion proves the jet effect of a mass of ejecta blasting in the direction of the shot. The second head shot is in slow motion. We can see the entry of the bullet and a jet effect spray in the direction of the shot. We also see a massive explosion on the front of the head which one might argue is a natural exit wound to the front of the head (which no doctor saw at Parkland). And then what happens? Why the head rolls over in the direction of the shot. But that roll over was not a head snap, it simply rolled over which might be due to any number of factors including a tilted table, an out of balance head, or whatever other magician's tricks might accomplish. The shots also appeared to hit directly in the middle of the heads. But what if the shots hit on the right temple? Would that not also make a difference in the way the head might react? The reaction of the head may also be due to reasons of Physics as explained by Penn. But one thing that head does not do -- it does not "snap" back in the direction of the shot from the back as Penn would argue K's did. It simply rolls over. Nor do we know how many tries Penn and Teller attempted before achieving the desired result. But we do know that the two heads in the demonstration, had two very different reactions. An observance of the Z film, and application of common sense shows that K's head snapped to the back because he was hit from the front -- from the Grassy Knoll. And the massive blow-out in the back of the head, observed by 40 plus on the scene witnesses, prove it.