I'm using a transform constraint not a parent constraint, but that's a preference thing, I'm guessing you could get pretty much the same result with a parent constraint. With the transform constraint I know that the IK control's parent will allways move exactly to the reference locator on the object. I only have one deform…
I've made a setup like that. Basically I let the IK conrol for the hands follow the object in question and animate the position of the object. I have the IK control of the hands parented to a locator that has a transform constraint to the objects bone. That way I can animate the position of the hand freely even when it's…