Joe,
I don't know about this being technical, but the most obvious thing regarding hanshees is the narrow blade, the thin double handed grip and the simple and sometimes shallow cho with a small protrusion.
A hanshee isn't neccesarily part of a 'circle' like the M43. Some hanshees have an extreme curve angle, while others are as shallow as a sirupati. In fact many of them are identified by the slight shoulder which is best found by feel rather than sight. I always run my hand along the spine with my eyes closed to find where it is and how extreme the angle. A very subtle piece of blademaking.
The grip is always a single piece with a partial tang whether it is wood, metal, horn or ivory.
Ah, compliments. Skeletor, you know just how to get me to post more images of my collection. Now if I could just get BEO to take all the pictures and you would have the best of both worlds.