A single bullet?

Dale Meyers explains in the video that he believes the second shot hit Mr. Kennedy and Mr. Johnson. First, the bullet hit the president and travels through his back and out his throat. Then it continues to travel through the governor's chest. Mr. Meyers supports this theory by using the Zapruder film, and turned it into an exact computer simulation. He also says that after pausing the frames of the film, both of the men react at the same time. After watching the video i do not agree with Mr. Meyers. I think that both men were hit by more than one bullet. I also think that Lee Harvey Oswald was not the only shooter and that he probably planned it with a group of people, and did not act alone.