Two things.
If you Google 'skull xray' you won't find any where the bone in the "blacked out area" is not clearly visibnle. Dr. Grossman says the JFK xray does not show mean those skull bones are missing but instead the blacked out area is an artifact of the effect of contrast applied when the xray was reproduced. In the Google samples not only do the entire skulls show, front and back, but the front does not generally appear to be a lighter bone than the back. Again, he is the expert not me, but I wish I could see other examples of actual xrays that correspond with his remarks.
Second, if you are a videographer, we don't care what the audience looks like.
