As per tite, some descriptions of buildings are completely duplicate, while others vary just slightly. It looks to me that the descriptions should come from the mod, and only come from vanilla if the mod doesn't have its own, as the mod's ones seem to cover the differences, if it's not actually intended to have the dupes.

Tested with v4.0.23 and just the mod installed, it comes from here

Included screen shots

screenshot gallery [imgur.com]