If you have one Bone manipulated by an ik, turn the IK off, then move the bone, the bone will always spin towards the ik in a anticlockwise manner.

meaning that if the bone needs to rotate 1' clockwise to point at the IK, it will rotate 359 anti clockwise.

If this wasn't bad enough, occasionally it will miss the angle and go past it meaning it needs to rotate all the way around again, and again and again.

worth noting 2 bones behave correctly