Remember the events of that crisis well. Lived just north of San Francisco. Knew a lot of the bases around the bay, naval, air force, army, and figured out real quick, if it happened, it would be over quick. Of course it didn't happen, or would not be here writing this.

As for the Zapruder film, if it starts at or just before the second bullet, then it works out that Oswald was indeed the only person involved. If not, it is a mystery for the ages.