I don't think it's that simple. A bullet could enter at the 6 o'clock mark from many different angles, thereby leading to many possible exit points and 'blow out' patterns.
Robert is aware of this. He even attempted to state that the mass ejecta visible on the Z film was sucked out of an entry wound by "jet effect" meaning a shot from the front.
What he could never explain, except through vague assertions of one or more film or photo being faked (with out showing any signs of tampering) why this "jet effect" and frangible bullet did not match the wounds described by his cherry picked statements and drawings.
We know there MUST have been a massive wound, ie a wound displassing a large amount of mass, because a sniper says the ejecta is from a frangible bullet making a big old entry wound. From the cloud of ejecta spreading out in all kinds of directions.
The ejecta, not being capable of quantum displacement and having mass, in a broad range of angles, a cloud in point of fact, can only have come from a big hole, as it can not have passed through areas of the skull and skin that are not damaged.
But wait! The best evidence apparently is the 100% accurated descriptions and drawings. Even if they don't match up to each other. Or the photos and films. JFK MUST have had a small entry wound on the front of the head. A small entry wound that would not allow for massive ejecta.
How does Robert explain how both these statements can be true? He wishes for a bird of paradise to align with the ejecta. The Z film is totally fake (except when its not and proves a frangible bullet).
Apparently refusing to explain how two conclusions that disprove each other can both be true is too difficult, but retracting either is impossible. Robert resorted to his catch phrases and denied there was a conflict. The apparent logical assumption being a frangible bullet hitJFK from the front, causing a small entry wound but blood, bone and tissue to think it hadexited through a big hole.
Further impossibilities abound. The z film must therefore have been altered to remove any sign of the exit wound on the back of the head. Robert insisted at length the back of jfks head was painted black to hide an exit wound.
He refused however to address how the exit wound ejecta, the stuff "blown out" was removed from the film. This would require a cloud of mass proportionately larger than the entry wound "jet effect" to be removed. A cloud that would obscure the background. Of course no explanation of how the background behind the car was restored, or why no ejecta from the rear is visible was forth coming. Instead it was stated it must have been there because Jackie can be seen scooping it up. Really.
So there is too much ejecta from the front, and too little behind. A theory that relies upon the same evidence it wishes to discredit. Hmm. Robert was in the habit of saying how evidence stands in court. What about when your experts discredit each other?