So I may have spurred Dotman to start this thread....
This is a widely debated subject with many different results for individuals. Here is what I have read, experimented and learned from world class archers and hunters.
For 95% of most archers shooting modern equipment the difference in elevation is minute and this is why. If you take into account elevation, you also must take into account temperature. Lower elevations are usually warmer than higher elevations, so some of the elevation difference is negated by the temperature change. The time of flight, time the arrow is in the air, on shots say under 50 yards is so short there isn't enough time for the differences in elevation and air temperature to effect the arrow significantly. That is the simple explanation, there are more wordy scientific explanations out there, but this should work.
Remember I said 95% of archers. Recurve, longbow or archers shooting slower bows, say 250 FPS or slower could actually see differences at longer ranges due to longer time of flight and their slower speeds.
An archer would need to be able to shoot groups in the 3" range at about 60 yards to even see the effect of elevation and it wouldn't be much, probably somewhere around an inch or two at 60 yards. For 95% of us, we can't see that difference as we can't shoot that well. At 60 yards, shooting a 5" spot, I may have a couple in the top of the spot, a couple in the bottom, one a little left and one in the middle. Say a 6" group, how would I tell which one the elevation was effecting with that type of grouping? I can't, but I know the animal I am shooting at is hit in the lungs and will die.
I shoot at 130' elevation for most of my practice. When hunting, the trailheads I hunt from to start my hunts are at 5000' and 8500'. I take my broad head target every year and send a few arrows downrange prior to heading out into the wilderness. At 40 yards, I will shoot all of my arrows into the lungs on a deer target without any problems due to elevation. And at 40 yards with broadheads, I typically shoot about a 4" group if I shoot the arrows well. I also shoot my arrow at 294 FPS. I know I am not in any type of world class archer status, so I fall into the majority.
A few years back Randy Ulmer, who I do consider a world class archer wrote an article on this very subject. I don't have it, but maybe someone can track it down and post it up. I don't remember it word for word, but this is what stood out to me. He made an adjustment in his set up due to significant elevation change. That adjustment was a half turn out of his limb bolts on a Hoyt shooting 300 FPS. That would equate to 1 to 1.5 pounds off of his draw weight or about 3 to 4 FPS reduction in arrow speed. Randy is an archer who can shoot well enough to see that difference at longer yardages.
Try that out. Go to say 40 yards and shoot a group of arrows, take a half turn out of your limb bolts, and shoot another group without pulling your arrows or marking them. When you went down to your target, I would say that 95% of us wouldn't know which ones were which.
I am not saying your crazy either about your arrows shooting a little high when you get into higher elevations on a hunt. But it may not be the elevation. It could be excitement, nerves, anticipation or you could be a 5% that is an excellent archer.
This is not that dissimilar to exterior ballistics in rifles. Time of flight is critical elevation effect on the bullet. That is why bullets with higher speeds and better ballistic coefficients are less effected than slower bullets with lower ballistic coefficients. Most flat shooting rifles don't need to start taking into account elevation change until about the 450 to 500 yard range based on all the same information.
And like anything on a forum, just my opinion based on my experiences.