[ashe]

the way i see it (practically speaking) there are only 4. the difference is the number of axis we're working with.

in frontal and horizontal planes, we have two axis (basically the shoulder joint)

in the saggital plane the elbow basically becomes the axis and due to it's hinge nature the range of motion is naturally more limited and so we go from 8 down to 4 circles.

although the Sifu as intimated that it IS POSSIBLE to create more than 4 but that the level of coordination needed is extreme.