Please vote and feel free to post why you voted the way you did. Thank you.

I don't believe so. It was always my interpretation (and I never read any literature that may have established otherwise) that Vader really sets off Luke by threatening Leia; Luke is overcome with rage, which he then unleashes on Vader. It is through the dark side, momentarily, that Luke is able to become powerful enough to defeat Vader.

If you look at the fights in the old movies, that part is the most intense. I believe we're to take from it that Luke's thrashing of the lightsaber bests Vader. Just the way that he's kind of growling at Vader and the look of satisfaction as he puts his sword to Vader's neck indicates that he is not exactly himself. He realizes this when he looks down at Vader's severed hand and recalls the duel in ESB. The Son becomes the Father, so to speak.

"I am a Jedi, like my Father before me."

Well, it was in the script, so, yeah he let him win. But if you are going for an answer that relates to the actual story, no. Definately not.

Luke dug down deep and pulled out his inner maniac to beat Vader fair and square. I think that by the time ANH comes around, Vader has long ago wiped out the majority of resistance in the galaxy. He looked like someone really good who was out of practice. In ESB he looked like he could have beaten 3 ROTJ Lukes, but he looked really tired of it all by EP VI. Luke got to be an okay swordsmen as Vader was sliding downhill. Right place at the right time. So no, Vader didn't let him win, but he didn't put up the defence of someone looking to win if that meant killing his own kid.

I was going to say, that inner beserker helped him a lot. Vader was old by then, and slow.

I think Vader was doing his best to keep face in front of the Emperor rather than letting his boy get the best of him. He threw his lightsaber with every intent to bring Luke down and it wasn't until he watched Luke being hurt that the good in him showed through.

definitely not, and I agree with everything said previously. It was Luke's rage that Vader had threatened to turn Leia, he probably would've killed Vader right then and there and really been screwed if it wasn't for the emperor opening his mouth and snapping Luke out of it. Vader was like a whipped dog when he got to his feet and I don't think he even had the strength to stand much longer until his own rage snapped watching Palpatine killing his son. I think he was disgusted at how much he had given up for this disgusting evil shriveled old man and wasn't about to give up his children and the last link to his past life as a good human being. He drew the last bit of strength he could from the force and tossed Palpatine into the power shaft, but up to this point he was fully prepared to turn or kill his son. I think he actually wanted any reminder of his past gone until that last second.

For the ROTJ duel, I agree with what everyone else has written. Vader was defeated.

I think a better question would be whether or not he held back a little bit in the ESB duel. I think he did. It's not until after he gets knocked off the platform that he starts taking Luke as a serious threat and, ah, disarms him at his first opportunity.

Yes.

No.

Vader is obviously taken aback by Luke opening up a can of Jedi whoopass.
Luke totally unexpectedly beats the living shit outta him.

Then it is Luke who holds back, regains his composure, and tosses his lightsabre on the floor.

I disagree. However, I will not argue the point. I've done enough of it over the years. People can believe what they want. After the prequels, well, it doesn't matter to me anymore.

Palpatine says to Luke "Gooood. Your hate has made you powerful" right after he's just overpowered Vader.

Just read the ROTJ script - it's all in there.

I think its a combination of the two... Sure Luke drew from the Darkside and went all ape-shit on Vader, but I think Vader's heart wasn't really in the fight, especially since he would have sensed Luke drawing on the Darkside and that prolly is a bit of a turn-off.

I agree with Topeka. Once Vadar saw the injured Luke, his rock innards turned into a mushy gooey center of love and goodness.