Excellent thread subject; articulate postings!
There's benchrest competition accuracy and then there's hunting accuracy. I can shoot 5 round, one hole strings all day with my benchrest .6mm PPC. I can't do that with a hunting rifle - why should I have to?
Ethically, I never shot at distances I did not feel comfortable with. If an animal was within a certain distance (different for various types/sizes of animal) and I knew, with certainty, that I could reliably hit that kill zone region, I would take the shot.
On whitetail deer, for example, I visualized a kill zone of about the size of a volley ball. If the conditions were right and I knew I could hit that size of target, only then would I take the shot. A minute of angle kill zone never entered my mind.