Vader rotj

Why does it seem like Vader just gave up fighting Luke? I have seen this numorous times and now its starting to bother me. After Vader says he will turn leia to the darkside if luke doesn't turn, and luke starts fighting with anger. But when Vader and luke reach the bridge vader seems to spin and purposely land on the rail allowing luke to cut his hand off. It just seems so poorly fixed to me. It looks so bad, has anyone else seen this or atleast bothered by it.

 

I'm bothered by it, but I figure maybe it means there was more happening than meets the eye. What if Palpatine started somehow interfering on Luke's behalf? He definitely wanted Luke to hurry up and defeat Vader.

 

I think Vader's desire to turn and/or defeat his son was simply waning by that point in time, whether he realized it yet or not. And there was likely an element of surprise in there as well. The intensity with which Luke launched his attack, and the fierce anger he was using to channel it, probably caught Vader a bit offguard.

And who knows - perhaps he felt that Luke's anger towards him was justified in a way. I think by that point he hated himself more than anything, and self-preservation wasn't a priority. Who knows what myriad of emotions and thoughts were going on inside of Vader/Anakin at that moment in time. The wondering is what makes it such a powerful scene, IMO.