Well that's....interesting. I only played Hanzo, so I really didn't read anything that'd seem like it was worth removing. But keeping the actual dialogue still strikes me as odd. It's like with Jojo's Bizarre Adventure: All-Star Battle where the name of a stand or person was changed (i.e like "Aerosmith" to "L'il Bomber") but the voices were kept the same so they STILL SAID THE ORIGINAL, CORRECT NAMES.
Hell, speaking of which, why not change the subtitles, then? Sure, it's lying, but at least people would have a jest of what's being said.
They don't want other to jump on them for "bad translation", I guess. It's not like there are no one could understand Japanese and still play the Eng version.