They know, or at least they should know, that a bullet struck JFK's upper back two inches to the right of his spine and exited from near the center of his throat. Their animation showed that bullet would have struck JBC somewhere depending on where they positioned him. They moved him from various positions from directly in front of JFK to well to the left of JFK. They showed the bullet striking JBC just to the left of his right armpit when JBC was slightly to the left of JFK, exactly where he was when the bullet hit. Since we know where JBC was actually struck, logic would dictate he must have been slightly to the left of JFK when the bullet struck him just to the left of his right armpit. Since they provide no explanation for why they determined the SBT was impossible, we are left to guess. My guess is their simulation validates the SBT. It does not refute it.
"...........logic would dictate he must have been............" The above is It is Not FACT. It flies on the Ed Forum. NOT HERE!
The back shot came from a storm drain all right, but it was the drain at the corner of Elm and Houston, not below the GK.