group placement - foot ctrl setup 3

Q.
1)Why are there ik handles connecting the ankle to the ball joint and the ball joint to the toe joint, when they are two joint chains (ik handles need 3 joints in order to calculate the movement)?

2) Why group the IK handle to itself and not the ball joint to itself

A.

1) Because the IK handles control the rotation of the joints, and keep the angles of relative proportion when rotated at the ankle joint.

2) IK handle again maintains the length and the angles of the foot rig so it behaves naturally. When a joint chain has an IK attached to it, you can still select the joint and it will behave in a forward kinematic fashion, so if you group the joint and not the IK handle, the group will behave like a forward kinematic rig. (see illustration below for example)