How big of a gap is Vader's power between TFU and ROTJ?

What do you guys think?

I honestly don't think he'd improved all that much.

I'd say the gap is noticeable, but not massive.

Prolly, but not by much really.

The Maul vs Vader fight is complete BS btw, so it shouldn't be used to answer this question.

I think it's a pretty big gap personally.

He declined by quite a bit.