Bone whose movement is tied to the furthest of two other bones? I have bone A, and Bone B, which both move forward.  Can I create another bone, C, whose forward movement is determined by the furthest of A and B?
You can use drivers: in my example I'm driving Y loc of bone C as maximun value between Y loc of bone A and Y loc of bone B.

Y loc is intended in local space, so bones are moving along their Y axis (Z world).