Hi Berkley,
I can see that is a possibillity, one I considered before posting but, several design features don't seem to add up.
If this object was to be mounted vertically (point up) having one fixing hole would not be very secure. The weight would try and rotate around the fixed point. More secure would be a minimum of two fixing points. The same scenario if mounted horizontally, less important if the object was to be mounted 'point down'.
One solution, to only have one fixing hole and making it secure, would be a shaped recess which prevented the 'rotational' forces, using the one hole to keep the 'object' in place.
The tail has a flatterned diamond shaped cross- section and an arc in the end section. To accommodate this securely it would be fitted into a slot with the same diamond cross-section, not an easy thing to manufacture, and unnecessary complication. As I mentioned before, I think, there is an unlikelihood of this ever having a shaft, as it would be better and much more advantageous to have the tail flat to fit a simple slot.
This is certainly becoming a "mystery item"
Link to auction...
http://cgi.ebay.co.uk/HUGE-RARE-MEDI...item5195221a99
Kind Regards David