Using Whitefeet Parameter Math tool to copy a untaggable System parameter into a Shared Parameter

In the image below, I show the basic process used to drive a Floor Area parameter into a manually added shared parameter.  Obviously, this scenario is not ideal - the data link isn't dynamic, so we have essentially created a mini-silo (that's what I'm going to call "in-software unlinked BIM") right inside Revit.

In any case, here is how you can quickly do it with Whitefeet tools (start at 1 and follow the arrows):



I previously posted another workaround for this - using a filtered schedule:
Tag Floor Area in Revit workaround