Posnansky (whose book I have just reread) has - I think - more to add:

"The maximum degree of stylization of the Third Period can be observed in the idols which we have called, owing to their special form, 'anticephalic'..."

"Moreover, the new idols are 'real columns'..."

"The only way to explain this new conception of the 'Goddess of the Moon' would be as follows: they saw the moon come up in the east or behind the eastern mountains, and almost in the same spot as the sun comes up in the morning. They saw that it passed in great splendor during the night through the firmament to set afterwards on the opposite side in the west.

Since the new conception was no longer in the form described before but was that of a true goddess with humanized features whose face and aureola stood for the lunar rays and light, and as this goddess could not go down or set on the other side of the firmament with the head, they then had the new idea of the 'double goddess' or the 'goddess with two bodies' of which the upper also went down on the side of the feet."

Regardless of whether we agree with this explanation or not we have here an example of 'columns' (i.e. 'poles' or 'posts', toko) with 'feet' at both ends or 'head to head'. Given that these 'anticephalic idols' represent the moon, I find it not strange at all to picture them as a pair; moons must be counted in twos. That they are mirrored - head to head and feet at the ends - might be explained in other ways too, as I have described in GD71.