Game Mechanics: Sneaking + Dragging Corpses

[sellingrandomcrap]

This seems to be failing for me more than it should and i have noticed a lot of times i don't pick up aggro when going by a mob until a /corpse macro is hit.

I was wondering if there is a possible bug between sneak and /corpse or is this intended / normal / I'm just a baddie.

I understand some mobs have a chance to see me but it just seems it is happening too often when dragging.