Forum:KB:Darth Vader's lightsaber abilities

It is common knowledge that Anakin Skywalker is the most powerful known force user (at least potentially), but what I don't understand is how much his powers weakened when he lost his limbs and put on the life support armor. According to an article on this Wiki, Anakin was "forced to change his fighting style" upon being transformed. So heres what I don't understand, is he just as powerful in the suit as he would be with a complete body? It seems like if Luke defeated him after training lasting only a few years than Vader couldn't possibly be as powerful as he would be if Obi-Wan didn't chop him all up. I would like this confirmed with a little more evidence if possible.

Note: The place where i'm typing this says "editing" and i'm new to this website, so I apologize if this doesn't show up in the knowledge bank. Hopefully it does and I haven't just created an article with a question rather than an answer.