I shoot 3D occaisionally with a guy who won the IBO National championship a few years ago in "barebow" class, and he described to me the method of aiming and it is exactly what was described above of "gapping" using the end of the arrow as a reference.
He said he could shoot accurately out to some long distances even by 3D standards.

So this leads me to assume that if you were to go to an "instinctive" gapping method of shooting a compound hunting bow that you would be best served by selecting and cutting your arrows differently than you would for conventional sight shooting?

I know it's almost funny to see the length difference between my full length recurve arrows and my compound/sights arrows.