I use to not believe all of the JFK Grassy knoll theories until I watched the Movie JFK. It convinced me that there was something to it. For years I believed Oswald was a patsy. Then I found out that Oliver Stone fabricated many of the so called facts in JFK just to make the Grassy Knoll theories more believable and the movie more entertaining.
Making these things up doesn't change history. Either Oswald acted alone or he didn't.
However since this film was pointed out to me, I loaded into Premiere Pro by Adobe and was able to blow it up and look at it frame by frame.
At full speed when JFK is shot it looks like his head is going back and to the left (hence in the movie JFK, Back and to the Left, Back and to the left, Back and to the left.)
However If you toggle between frames 312 (the last frame before the head shot) and frame 313 (the first frame of the headshot with blood and brains flying) you will clearly see that JFK's upper body and head is being thrown forward and down at least 6 inches from what I can only conclude is from the force of the bullet being shot from above and behind. Its too sudden and violent to be anything else. (in my opinion)
Its only between frames 315 and 323 that JFK is being thown back and to the left. I don't know if someone else shot from the front, or this is just from the violent impact of the bullet making his nerves flinch, or from some other high speed ballistic cause, but frames 312 and 313 are the ones of interest here, not the rest.
I'm now back to doubting the Grassy Knoll theory. I still down know who shot JFK, but the head shot is almost surely from behind.
Its interesting what you see on your own when Oliver Stone isn't leading you around by the nose.