After further thought I think it has a lot to do with mob and NPC movement changes updated recently.
When fighting mobs I notice their movement is slightly more erratic. Actually, its a LOT more erratic.. for example kobolds will zigzag toward you and dance around very erratically until they actually attack, at which point they disengage and zigag around even more. Like they're on steroids or something. All mobs are like this now. Heck I just fought the entropic giant and it was like it had ants in its pants, it couldn't stay still for a single second.
It didn't used to be like this; before, the enemy would approach, engage and the fight would commence without the zigzagging, chaotic or jerky movements added to suggest 'combat realism'.
So no, the chaotic/jerky movements idea does not add realism to the battle, instead all it does seem to add is
You are not facing...
You are not facing...
You are not facing...
I'd suggest devs adjust the movement code and roll it back to how it used to be to get rid of these annoying error messages.