The primary reason many (most?) of us don't use the heat deflector stone(s) is that they just add to the heat-up time (and more charcoal burning) for not a very good reason. You're mainly just trying to shield the food from the direct infrared heat of the fire for indirect cooking, so just a simple sheet of AL foil will do that, and it catches the drips, so you won't have to mess up that SS pan.