Got this one by accident while going for The Darkness achievement. Load up Ch. 7. Make it to the 2nd area. As soon as you start, head towards the house straight ahead with the open door. On my game there were two guys literally walking shoulder to shoulder with each other on the right handed path. I snuck up behind one, held
down to preform Shadow Kill. Apparently the animation for shadow kill ability was long enough for his buddy to turn around, spot me, and kill me just as the animation was ending. So I got both The Darkness, and Dishonored achievements at the same time.
Hopefully this helps and you get the same pathing from the enemies I got. I've noticed that sometimes when you load a chapter up, that the A.I. is sometimes in different spots.