The "topic" of James Files does not upset me at all. However, he has been dismissed as a fabricator. To be clear: "There was no abort team in Dealey Plaza" that day. This type of Operation does not work like that. Roselli did not fly into Dallas to call off the hit. The story reads like a novel rather than an Executive Action. If Nicoletti had been instructed to stand down, why did he go ahead against orders and risk immediate termination? Why would Files, knowing that the hit had been aborted, agree to be the "back up" shooter at Chuckie's request? BTW: There is no such thing as a "back up" shooter in the first place.
It would be like watching an American football game where the Quarterback scrambles out of the pocket while the opponents are in pursuit. He approaches the sideline with nobody open to catch the ball until the last second. Just as he throws his pass avoiding a sack...another "back up" Quarterback enters the game from the far sideline and throws a 63 yard touchdown pass to the SAME receiver, both footballs arriving at the same point in the end zone at nearly the exact same moment.
I further submit that--even if such a "back up shooter" scenario was credible--this cast of characters lacked the Professional Tradecraft to have accomplished their assignment.