Of course, I haven't read all the information about the JFK assassination. And often, including thanks to your forum, I find new information about it.
In particular, I came across information about Gordon Arnold here. According to him, some, may be fake Secret Service agents had been clearing the parking lot on the Grassy Knoll from outsiders just before the motorcade passed through Dealey Plaza. Another brick in the Files' version. And it seems that other witnesses besides Gordon Arnold have testified about this.
Because if you believe in a conspiracy, then when shooting from behind the picket fence, there should be no outsiders nearby.
And it repeats itself regularly. You get new information. You try it on to the Files' version. And... it fits it.