This is intriguing. The lenght of pulls for many of the posters it seems to me is quite long. I agree with the idea that if your eyes are closed as you shoulder the piece, the sights should be aligned and on target when you open them. My own rifle stocks are only 13.5" and I'm 6'3" and 240, but I carry alot of weight in my shoulders. When I do shoot with a longer stock I am concerned with the butt catching loose or bulky clothing. This could be a real problem on a "serious" rifle. I suppose if you train yourself to push the rifle straight out, as one would a shotgun, then pull it back into your shoulder this danger is eliminated, but for me that is too many motions when you are in a hurry. My eyes are fixed on the target, and the rifle comes straight up until the butt hits my shoulder and the sights align.
Mike