Right.  The alternate approaches don't seem to have anything immediately resembling the test you use there, yet they don't seem to suffer from dropped matches or false hits.  So I wonder whether a different approach might be applied to test whether we're in the tri which might somehow avoid the need for the sensitivity test.  On the other hand, I'm not sure I understand what they (or you) might be doing in every step of the code, so I could easily be overlooking something.

Really, it might make some sense to make your hueristically determined sensitivity value one that the user can set, to alter or refine results based on the needs of the meshes being compared.  Or am I wrong in thinking that?  I know the script is already pretty confusing for the user (which is largely a GUI design problem), and such a setting might make things more baffling rather than less....

Hmm.  See, you're still the smart one in the thread.  :D

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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.