That’s helpful in regards to Luke, sorta. The imperial rewrite of history explains a lot, but I still have misgivings about how all this actually plays out.

Regarding Tarkin, it makes sense he would know, but I was referring to the other guy in the council room who tries to goad Vader about the Death Star being better than the Force and his “sad devotion to that ancient religion” This line implies that he considers Vader as somehow connected to the “Jedi”, if anything wouldn’t he think of Vader as Sith?