I'm probably not going to explain this as well in text as it plays out in my head, but here I go anyways: As wise as he was, in the PT Yoda was just as much a victim of (and, dare I say it, even blindly supported) the corruption in the Jedi Order. In the OT Yoda is more of a 'pure' Jedi (much like Qui-Gon and Luke), but even still he was bound to some of the trappings of the old Jedi Order (he believed that Vader should be killed, not redeemed). Still, Yoda was wise beyond his years (which is crazy, since he was almost 900 years old) and was one of the most powerful and influential Jedi ever. Also, I don't really understand why everyone finds Yoda's use of a lightsaber in the PT as contradictory of what he stated in The Empire Strikes Back. "Wars not make one great," Yoda says to Luke on Dagobah. As someone who had unwillingly fought through a violent, corrupt, unbeatable conflict such as the Clone Wars and lost due to his Order's very blindness and arrogance, it makes sense that in his exile he would try his best to lose the trappings of the old way and surrender himself completely to the Force. Only though his exile and Qui-Gon's teachings was Yoda able to transcend the Jedi Order of old and completely come into his own as the wise sage that Luke meets on Dagobah. I can't choose between Prequel Yoda and Original Trilogy Yoda. Much like everything else in the films, he underwent a very natural transition from one trilogy to the next. As it stands now I can't really have one without the other. They complete each other, just as the two trilogies complete each other.