I have a 64", 52#@28" ACS CX. I'm shooting 30.5" Axis 400s and 29" Beman MFX 500s, both with 125 gr up front. The bow shoots both arrows like darts.I don't exactly put my heel on it, in that I grip the bow with the thumb and index finger circling together, but the meaty part below my thumb is on the bow, not the centerline of my hand, which I would take to be the heel of my hand.
I just have to focus on a steady bow arm, focusing on the precise point I want to hit and getting a crisp, static release. If my release hand goes flying or dropping, the arrows follow suit! I also purpose a draw with my back muscles to get the maximum draw without over exaggerating it, if that makes sense.
Bill