Although I have no proof that this it happened, I have often wondered if President Kennedy gagged once the bullet ripped through his throat, thus he threw his hand up and over his mouth. He makes two jerking motions as he exits from behind the Stemmons sign. The first is a very sudden head-nod motion, and the second looks like a possible gagging/heaving motion. I made a similar post to this group a few years ago regarding JFK's hands, and one of the people who read the thread pointed out that it looked to him like JFK wipes his mouth off as he's turning his head to his left. Since then, I've wondered myself if he didn't do this, and wondered if JFK could have both gagged on blood in his mouth, and the terrible feeling he must have suffered as the bullet tore through his throat.
That does not look to me, or apparently to most other medical professionals

, like an intentional series of movements. "I am gagging and am going to wipe the blood off my mouth now." That looks to me like a completely reflexive (i.e., Thorburn-like) reaction to a neurological stimulus.
The analysis of Altgens6 looks suspiciously like pareidolia to me. I'm not convinced we're seeing his mouth at all, let alone in the level of detail being suggested. I brought this up to maximum magnification on my screen and examined it with a magnifying glass, and I was still left saying "Ya got me." I did see Bogus Haygood Imposter there in the corner, however.
