"That's incorrect about the closer the arrow pass to center the more you can heel the bow. It's the other way around."
"You are however correct about needing more positive tiller when heeling the bow."
This is the crux of my confusion, although I'm not yet convinced I'm wrong. I have long held, in my own debates w/ myself, that placing the arrow pass at dimensional center tends to mitigate the need for positive tiller. That they have the same effect, of reducing the asym inherent in drawing the string above where we put pressure on with the bow hand. By simply comparing two strings, one from a bow with arrow pass at center, another 1" to 2" above, one can see this exaggerated assymetry in the latter example (above center). By having unequal limb lenghts, we're forced to bring the bow back into balance by using the spring force of each, specifically by reducing the upper to let it bend farther because it is inherently shorter. I believe having the arrow pass closer to center helps put the nock point on the string closer to center, and thus reduces the need for positive tiller. But to be honest I have not resolved the issue completely for myself.
Seems like heeling a bow exaggerates this asym, and requires more positive to combat it. And if placing arrow pass closer to center combats it (as yet unproven in my thinking, but the idea I'm currently entertaining), then one might conclude having the arrow pass closer to center helps combat heeling in the same way as positive tiller. I base this on the spring strenght theory, as articulated by Tapley, and it's impact on nock travel, and the resulting incentive to positive tiller.
We may just be having a semantics disagreement, where we're saying the same thing in different words and perhaps don't realize it.
"Since there is no nock travel at brace I believe any upward/downward nock travel at full draw is irrelevant."
I would agree with you, were that my position. But it's not. Rather, my position is that the nock moves up or down as it moves along the path from full draw to brace during a shot. This I think is irrefutable. One can find lots of demonstrations all over the net, Paleoplanet for example had a thead recently. I was first exposed to it perhaps 8 years ago by Steve Harville. He may have is blog up still. But whether it is relevant is certainly subject to debate.