From Star Wars Made Easy, released three days ago:
The last time they met, Vader was more powerful than Luke. Now Luke has the upper hand, and can destroy Vader if he is willing to give in to his anger.
__________________ "There is only Revan. Only he can shape this galaxy as it is meant to be shaped."
Registered: May 2007
Location: Best company on the planet
Luke crushed him. I find it sickening when fans make excuses. Vader didn't want to lose and as soon as Luke got angry and actually fought with passion he decimated him. Vader is weaker than Luke.
The movie, which is canon and depicts Vader being heavily conflicted which would make him hold back quite a bit. It's also mentioned in the TFA novel how Vader had feelings for Luke and how they stopped Vader from killing Luke.
__________________ "Once more, the Sith will rule the galaxy! And... we shall have... peace."
Watch the movie. Luke and Vader have a conversation, in which Luke notes the conflict within Vader and asks him to turn back to the Light. Vader says, in a sad tone, that it's too late for him, indicating that he has some willingness to turn back to the Light but just can't or Sidious will annihilate him- hence the "I must obey my master."
And the TFA novel quote:
"Yes. Such a simple thing. Such a foolish error of judgment. A momentary lapse in an otherwise exemplary life. Had Lord Vader not succumbed to emotion at the crucial moment— had the father killed the son— the Empire would have prevailed. And there would be no threat of Skywalker’s return today."
__________________ "Once more, the Sith will rule the galaxy! And... we shall have... peace."
Might be? Probably isn't. That's the case based on the text alone.
The prepositions above describe the fight before Rage! Luke. Stating that he can give in to his anger to destroy Vader, but presumably isn't right now. So logically speaking, the text is referring to the fight before Vader initiates project probe.
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“We defeated the wrong enemy” - General George S. Patton, Berlin 1945
Registered: May 2007
Location: Best company on the planet
So your point is Vader is weak emotionally. I wholeheartedly agree he's always been mentally weak it is a crucial aspect to the character. Hence he jumped ship twice because he was an emotional mess at pivotal moments in his life. Luke was a lot greater in Rotj than in ESB in which he still grazed Vader's shoulder. Coulda, woulda, shouldas don't undermine the facts. He a human being with emotions and he got his ass kicked. Then he turned on the emperor. A delusional man weak to the end. Glad he died. Vader was weak. He died. The end.