I watched Star Trek: Enterprise intermittently when it aired and missed the two parter "In a Mirror, Darkly" until I watched it recently on a whim. It ties together two episodes from the original series and fleshes out a particular corner of Star Trek. It also raises questions if you think about it.
I'm a bit of a history buff so I think about stuff like this. Revenge of the Sith takes place about twenty years before A New Hope (19 years before the Battle of Yavin according to Wookieepedia ). But Han, Luke and many others seem quite ignorant of events before Order 66 was implemented.