It is a requirement of the second shot SBT and almost no one has been suggesting a first shot SBT - Dan O’ meara is the exception. Dan’s first shot SBT has fewer problems with the evidence but still requires rejecting the evidence of JBC, Nellie, Greer, Hickey, Gayle Newman and requires a shot after z313 to fit 3 shots.
Still trying to save your turkey of a theory? For months you were using Mary Woodward as your principal witness to argue that JFK was hit by the first shot and now we find out she has ALWAYS known that the first shot she heard didn't hit anybody. That takes you back to square one.
Dan O'Meara and Jack Nessan both seem to have a bee in their bonnets over an early shot miss. Unless I am conflating their scenarios with someone else's, I think they both believe a first shot single bullet followed by the headshot and no other shots. While the WC identified that as a possible scenario, I don't think they really believed that was plausible although I can't say for sure. To believe the first shot single bullet is to believe JBC was wrong about hearing a shot before he was hit and turning to look over his shoulder in response, even though we see him do that in the Z-film. While I don't see anything in the Z-film that directly supports Mary Woodward, her account conforms with JBC's knowledge that he was not hit by the first shot. JBC rejected the SBT solely because he was led to believe JFK had been hit by the first shot and he knew he had been hit by the second. I don't know what led him to believe that, but that is the belief he seemed to hold for the rest of his life. It follows that if JFK was hit by the second shot and JBC was also hit by the second shot, they were hit by the same shot. Mary Woodward's account dovetails perfectly with a second shot single bullet.