Hoyt, Jeff is absolutely 100% correct, aim for the exit hole.....all of us understand the exit hole area changes with each angle the deer is at and each elevation we may hunt from but it's still that simple,

AIM FOR THE EXIT HOLE YOU WANT! or AIM FOR WHERE YOU WANT THE EXIT HOLE, or AIM FOR WHERE THE ARROW PASSES THROUGH THE DEER AT SUCH AN ANGLE IT TAKES OUT THE LUNGS OR HEART AND EXITS THE DEER....

simple, aim for the exit hole!