Since he strafe by holding down his right mouse button and pressing A and D (bound to strafe left/right) the mouse "resets" to the middle of the screen and then "reappears" once a fight starts and he start healing.
via N4G: pc news feed http://n4g.com/news/1213955/mouse-movements-during-9-hours-of-progression-raiding
via N4G: pc news feed http://n4g.com/news/1213955/mouse-movements-during-9-hours-of-progression-raiding