My rule of thumb - broadside shots - come straight up the leg, hold crosshairs at midbody, squeeze the trigger.
If hit exactly broadside and in center of shoulder, they normally hit the turf right there, flop around on the ground a couple of seconds but generally aren't mobile.
If the shot drifts back a bit, you're in the armpit and they do tend to be mobile but not in any organized manner - your "chicken dance". I have had animals go much farther than I cared for. If the shot lands a bit forward, your break major bones, scapula, etc and they drop on the spot.
On quartering shots I tend to aim for the center of the off shoulder.
Not directly broadside - when I thought they were - has given me issues over the years. I shot a bear once that I swear was dead broadside. I watched it for 20 minutes before I shot it, had a dead rest over a log and shot distance of 50 yards. I distinctly recall squeezing the trigger - everything was perfect. 'Cept the bear was quartering to me a tad. Only hit 1 lung and liver. That bear went 150 yards with a 45-70 hole through it. 150 yards in the Canadian bush - I was lucky to find it.
