If the surfaces are matched fairly well, then raycasting is probably the better comparison option. I never had the tools to match areas like ears in a better than approximate manner, so I found the closest vertex approach suitable for such things.

That ridge along the edge is at the join between two merged comparisons, right? That's where you would want to use the "inclusive" edge setting for one side, and "exclusive" for the other. Then that edge belongs to only one of the areas, rather than both (or neither).

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Cage can be an opinionated jerk who posts without thinking.  He apologizes for this.  He's honestly not trying to be a turkeyhead.

Cage had some freebies, compatible with Poser 11 and below.  His Python scripts were saved at archive.org, along with the rest of the Morphography site, where they were hosted.