There is no evidence provided in the zfilm that is inconsistent with JBC not reacting to his chest wound before z255. His actions are quite consistent with the rest of the evidence, which is that there has only been one shot to that point. We have Altgens who was there and took the picture and confirms that. The problem is not with the zfilm. The problem is that the zfilm alone cannot tell you where the second shot occurred.
It tells people with good eyesight and a functioning brain when the second shot was fired that hit both JFK and JBC.
