Here's a bit more insight on this. Your video said "about 300 FPS" for your bow. So I found a buddy's setup saved in my archery software program of a Bowtech Guardian that flings a 391 grain Maixma Hunter arrow at 293 FPS at 72# draw weight and compared the flight times and speeds versus if he turned it down to 50# draw weight and shot the same arrow 253 FPS. The results:
Distance, Speed, Flight Time of 72# Draw Weight
0, 293, 0
20, 283, .208
30, 279, .315
40, 274, .423
50, 269, .533
60, 265, .646
Distance, Speed, Flight Time of 50# draw weight
0, 253, 0
20, 244, .241
30, 240, .365
40, 236, .490
50, 232, .618
60, 228, .748
My take is that at the ranges deer are normally taken (20-30 yards) the difference in time of flight is negligible and should not be used as a reason to shoot the lightest arrow possible and the highest draw weight imaginable in order to gain top speed. Most archers would likely be much more effective as a hunter with a very heavy arrow and much lower draw weight; heavy arrows equate to quieter bows and more momentum; lower draw weight equates to steadier holds, less extraneous drawing motion and longer windows of opportunity while at full draw.
As for trying to decide "how low to aim" there are way too many variables to stick with one set of rules. For instance, most deer are missed high from a treestand due to poor form rather than string jumping. Combine poor form with a bit of string jump, and you can miss an entire animal by 36". Our deer jump the string far less, as a general rule, than those in that video (likely from Texas where small, jumpy deer are famous). Mule deer jump the string less than a whitetail in the same circumstances. Elk rarely jump the string at all. (Although I did have a big 6 point bull entirely duck an arrow at 20 yards once; I heard his his chest literally hit the dirt.) I don't know anything about blacktails.
Experience is the key in deciding how and when to shoot at that particular animal in those particular circumstances.
