You are nit picking there! :)
Itxe2x80x99s a complicated one, but I believe that it might be possible to experiment with:
Automator (have an action that takes a PDF and modifies itxe2x80x99s metadata)
PDF Services (have a service that is xe2x80x9cSave As My AuthorLess PDFxe2x80x9d) ;)
AppleScript (Both/All of the above)
I suggest you google around those concepts. This is a good starting point. All in all, the idea of your script is to use the Automatorxe2x80x99s action called: xe2x80x9cSet PDF Metadataxe2x80x9d (you could then put blank data on purpose):
If you create a PDF Service capable of replacing the default one, but that also sets the metadata to Blank, youxe2x80x99ve won.