I concur with the wisdom of discussing these questions, the why's and how's, so we can be armed with more information when the occasion arises. One reason I would not take the quartering-on shot from the tree stand is I've never had a deer suddenly whirl and run while I was sitting still that high up in a stand..they keep walking and will present a better shot that doesn't implicate the shoulder bones. I also like the op including distances..8 yards away from a deer a row or 2 into standing corn is a world of difference from 25 yards away. The deer on the property line is always a tough choice and over the years has pushed my blinds farther and farther from the edge of my hunting property, which is a tough concession because some of my best spots have been along fence lines , for obvious reasons. While I may not take those shots, I hunted with old timers who had excellent arguments for a high percentage shot placement from every angle, based on a thorough understanding of the anatomy of the prey.