Character's IK Arm target lags behind when entire character is moved

3.3.1

I’m following this tutorial which uses curves and a Follow Path constraint, which seems to work okay, except when I try to move the character as a whole, having linked the entire character to a sphere empty. Instead of behaving like the left arm, the character’s right arm IK target lags behind the body, by a greater amount the more the large sphere empty is moved.

To recreate the issue, move the large empty sphere, which surrounds the character, forward or backward, and watch the character’s right arm’s IK target lag behind as the character moves forward or backward.

animation-skin-armature-test2.blend (978.7 KB)

Tutorial: