I think the higher levels are the main culprit, and I will go as far as saying perhaps it was a mistake. With optimal builds it borders on breaking the capabilities of the engine. Saw this before in the fall of 2011, when I and some others were level 40 and a few 40++
It's not as bad as back then though. You *can* block whatever comes at you, but the amount of times where swings seems to skip frames or hit out of the blue has increased.
It's tolerable, but some builds, with some weapons, with some techniques, should be a little bit slower.
If it can be reversed or fixed at this point.. now that's the real question. San, what you think?