IF you could put an arrow in the deer earhole consistently, why not just clip the artery coming out of the heart?
If you miss the artery by a half inch you would still probably get the heart. If you miss the theoretical perfect "earhole" shot that would put the deer down there's a good chance the arrow glances off. I think to be able to pull off a shot that good you would almost have to be able to robin hood every shot at whatever distance you would want to shoot the deer. You would have to be able to hit the 14 ring on every shot on a 3d range.
Why would you try to make an easy shot so hard? (heart/vitals vs earhole)
If the cover your hunting is so thick, why not cut some better shooting lanes? (if your hunting from a deer stand)
I had a cousin try a head shot at a doe at less then 10 yards with a compound, the arrow glanced off the skull.