Dang it, Roskoe. You're tryin' ta make me think again.... and it hurts.[>:]

When the tiller is set right, and the limbs are in balance, the arrow will be square to the riser, like this -|--<<<

Nock high would have the arrow crossing like this -/--<<

Nock low, the arrow would be crossing the other way -\--<<

The weaker limb will be closer to the shooter at full draw, bcause it's bending more. So, in the case of a nock point below square, the top limb will be too strong.