A JP pose just has all of the joint information for the figure.  The attached is an example.

So a standard library pose is helping correct the problem, but only if loaded twice?  Is that correct?

If any combination of poses is found to correct the geom insertion joint errors, you can try running all of them with one click, from a readScript pose.  Using readScript, you could run the geom insertion, then load the standard pose twice, if that's what's working.

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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.