Revealing mistake: When the doctor examine Ronnie's "corpse" in the morgue, he pulls out the stake. It is quite obvious that he's struggling with a wooden stake that is placed on the actor's side, not through his chest. Moreover, the camera pans up and you can briefly see Ronnie's unharmed chest.
Revealing mistake: During the autopsy, right after Scully has the vision of her daughter, the body of Paula Koklos can be seen to move (watch her hands and neck). (00:24:05)
The Red and the Black (2) - S5-E14
Revealing mistake: It seems that in the first shot the doctor injects something into the vaccine vial rather than extracting from it since the syringe plunger is moving inwards instead of outwards. In the next shot one can see that the syringe is being filled with the vaccine, however the arrangement of doctor's fingers is suitable for injection, which strongly suggests that the scene is played backwards. (00:17:55)
Schizogeny - S5-E9
Revealing mistake: A heavy rain is falling but there is no sign of it on Mulder and Scully. (00:32:00)
Kitsunegari - S5-E8
Revealing mistake: When Scully pries open the mouth of the man who died from being forced to ingest paint, his eyes twitch. (00:13:50)
Revealing mistake: The dead Mrs. Sim is supposed to be nude in the bathtub, but for a brief second, a glimpse of her head and shoulders reveals the very top of a flesh-coloured modesty wrap covering her breasts. This may not be visible in a non-widescreen format release.
Answer: He was being facetious. He doesn't specifically know that information, he was merely giving examples of the types of information he has access to.
I think so too.
lionhead