If, as some people contend, there was a large hole on the right rear portion of JFKs head and a corresponding small entrance hole at the hairline area above the right eye (presumably this would require a shot from some area in the vicinity of the triple overpass in front of the limousine), then shouldn't JFKs head have snapped back and to the right rather than to back and to the left as we see in the Zapruder film?