I think I usually have had the distance cutoff at 2 or 3. A setting of 1 will give you a 1:1 comparison, which is (or was, before Poser transferred morphs natively) useful for moving morphs between multiple instances of a figure or object within a scene. The more samples you use, the less precise the transfer is, on a vertex-to-vertex basis. I believe that distance in Poser Python is always in Poser Native Units.

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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.