Generally the need for precision in this alignment increases as the distance to the target increases. A lot of gunfights with handguns actually occur at ranges of about two arm's lengths or less. At the very closest of ranges you could actually hold the muzzle against your assailant and put the bullet into him. It might not go into the most disabling part of his anatomy, but you could say that you aligned the bore to the target by touch. As the distance grows you can still get a fairly good alignment with a target which is not moving radically merely by body position.
Body position is, in fact, a component of precision, sighted shooting.
NPOA is the orientation of your body to your target for the particular position you are shooting where, after you have obtained your sight picture, you can close your eyes for a moment and still find your sights aligned with your target when you reopen your eyes. When you train repeatedly with the NPOA, it becomes natural to adopt that orientation toward potential targets. As your distance from the target increases it usually becomes necessary to use a visual index. As the distance continues to grow, not only do most people need to use the sights to align the gun with the target, but they need to use them with increasing care as the distance grows increasingly longer. Keep in mind that circumstances other than distance may also increase the need for precision.