Considering lesser opponents have been capable of briefly dueling Luke/Yoda/Sheev (i.e. Dooku, Maul, Gaalan), I never believed Yoda/Sidious/Luke were so ridiculously untouchable that they could blitz Vader. Sidious didn't show his full power and is still Vader's clear superior, I really don't see a problem with anything having to do with the power disparity between them in the Disney continuity (aside from the Vader>Sidious in sabers quote depending on how seriously you take that, which I don't).