I haven't read the whole post and I am no expert for sure but I've killed a few deer with buckshot and my family has taken a lot with it. Louisiana has never been a buckshot only place but it was a preferred choice when most deer hunting was done with the assistance of hounds that were bred just for that purpose. Don't worry about the "poor little deer." Deer were never run down and killed by the dogs not was it a pot shoot where every deer that the dogs ran was shot. There were a lot more times that the deer were not bucks and were illegal to kill. Many is the time when a buck was seen and never presented a shot. The dogs were used primarily because of the briar thickets and swamps were there was zero chance to still hunt. Buckshot was the right tool for those circumstances and it got the job done. Now I will get off of my soapbox.
Buckshot is a funny animal so to speak. You could have two identical shotguns that patterned buckshot completely different. 00 was/is what most people think of when buckshot is mention but it is not always the best choice. For example, my brother's 870 would not pattern 00 at all but No.1 was deadly with tight patterns out to fifty yards. I found that my old 12ga. would pattern well (repeatedly) with 3" magnum 00 but only if it was the Winchester unplated, buffered kind. Inside 30-35 yards a shotgun that patterned well would drop a deer insight of the hunter if he had done his part. In my my experience out to 50yards a deer wasn't going far IF you had done your part to find the right load and shot true. By that distance buckshot per pellet energy is getting low and is losing it fast. Sure, someone would make a freak shot and kill deer at 75 yards, or if they lived right, further. Before you call me a liarremember that we were using dogs who could follow them up. I've read all my life about how useless buckshot is past 25-30 yards at most but I've got generations of hunters that say that isn't so. One writer in a "tactical" article wrote that, "buckshot will not go through a leather jacket at 70 yards." I realize that is a looong way for buckshot but no one could get him to put on the jacket and let someone take a shot.......
