At first it seemed like they were going to have Palpatine's aging into the corpse we see in ROTJ be gradual but aggressive, probably from being so deep in the dark side. At some point they changed their minds and it mostly came down to the result of the duel with Mace Windu.
C3PX: I'm sure Uncle Owen, Aunt Beru, and Obi-Wan would look like hand-me-downs if set beside people of the same age from let's say Bespin or Coruscant. And where would you get the impression you'd stepped on my toes? What?
Sluggo: I agree, but even if I didn't like a retcon, I wouldn't label it an outright "error" as long as it could be explained with sound reasoning.