When dealing with additional shape files (e.g. for a feature layer for German postal codes) it would make a lot of sense to be able to store this information centrally in the library rather than having to provide a "shadow" library in which the shape files are shared amongst analysts. Also this would remove the necessity of embedding the shape file data (which can be fairly large) into the actual analysis, thus resulting in a smaller size of the analysis file.
For whatever reasons the performance of the solution provided is pretty slow when doing it in this manner at least from the tests I have done. There is also an alternative you can use if you can load the file into any database when storing the geometry as a binary field. When you do that you can simply set up an information link to the database and pull the data in that way and then use the same steps with x-min, x-max, etc. when you pull in the table.
Seems to be "solved" using this community article. Thanks to Arnaud Varin for pointing this out.
https://community.tibco.com/wiki/expanding-spotfire-geocoding-coverage
Also relates to
https://ideas.tibco.com/ideas/SPF-I-4904
and
https://ideas.tibco.com/ideas/SPF-I-713