I remember seeing this really great documentary about the JFK assasination. Too bad I cannot remember what channel made it. But the people who did really did go to some amazing lengths to re-create what happened. They built a body simulaid of Kennedy and filled its head with a substance to simulate brain matter. Then they shot it from the same position that Oswald would have been at. Using high speed footage, they were able to show that the debris from the shot matched pretty close to the Zapruder film. And if that was not enough, they even brought a couple of witnesses who saw Kennedy's car and they said that pattern of brain substance was almost exactly like what they saw in the real thing. It was a pretty definitive documentary if you ask me.