I guide elk hunters in Northern Idaho. . . timber country, not open breaks. Practically all of our elk are killed in clearcuts, and the average range is 200 yards, we kill a lot at 300 and a lot closer than 200, but it averages out about 200. We don't kill a lot much over 300 for the simple fact most of our hunters are from back east and aren't comfortable shooting farther than 300 max. If I have a hunter comfortable to 500 or farther I have a lot more options on where to hunt, because if he is comfortable at 500 he is dang sure going to be comfortable at 50. I've killed most of my elk at over 400 or under 75, simply depending on whether I was hunting the timber or open. Because I'm comfortable out to 800 (longest range elk killed was 820) I tend to set up across the canyon from where I think elk are going to come out if hunting the open. You can usually see better and you don't have to worry about wind or movement so much. Obviously I can't do this with a hunter who has never shot a deer over a hundred yards and is comfortable at 250 at best.
I would say a heck of a lot more than 1% of hunters that have killed multiple elk have shot one over 300, even if it was only 315. Now if you are counting all those hunters back east that only hunt around home and live in states where they can't even use centerfire rifles, I still don't think we are getting down to your 1% figure, but we are getting closer.