oldgoat
WKR
I'm in this boat, I had to finish off a wounded moose a couple years ago, was able to get closer than forty yards, but if I hadn't I'm very proficient to 40 and even beyond IF my speed is sufficient and for me that's in the low 170's, you can crush all the bones you want, but if there's no vitals on the other side then it don't matter. Now if you were going for some kind of water buffalo, muskox or elephant etc, then that arrow might come in real handy!From my 14ish years with a recurve and all the folks I know who shoot one, that seems like the cut off point for who is genuinely good, and those who you hope the animal about runs them over.
I also think practice should regularly happen past the hunting effective range.
Lastly, I think that is a distance where form causes things to open up greatly. Akin to a 70 yard compound shot, or 500 yard rifle shot. If a person has good form with their trad bow the drop from 30 -> 40 yards isn't too much for the brain to compensate for "instinctively". If one is going heavy enough that their brain can't calculate the trajectory, I think that is a diminishing return.