I think some might have misunderstood your post - or maybe I did - but..... when in a treestand, you want to envision where the arrow will exit, same goes for a quartering away shot. Aiming at the lower 1/3 of a deer, from a steep angle will at best get you one lung, even if he does duck down. You want the arrow to exit the deer on the far side, in the lower 1/3 of the body - so yes - you want the arrow to hit the deer in the upper 1/3 on your side. With a quartering away shot, you want to aim for the opposite shoulder (which usually is like the last rib back - on your side) Shooting at a quartering away deer from a treestand - you want to aim for the last rib back in the upper 1/3 of the body, so it will exit in the lower 1/3 on the opposite side near the shoulder. Of course the less steep the angle, the less you must compensate.

A few minutes shooting at a 3D target from different distances in an elevated stand - will make it obvious what you need to consider.