First of all, my question is not quite the same as
Is Office 2007 PIA deployment possible without Office 2007?
I am not looking to use the PIA's yet. The IT engineers would ideally like to deploy the 2007 PIA's to everyone's computers before they upgrade Office 2007. This way there is fewer things that have to go right all at once. I am wondering if this is possible
My best experience is deploing PIA with your application/add-in, because there are some awkward factors, which can be solved by this way.
If you will not register them to GAC, and tehy will stay in directory of you application/add-in you will not affect nothing else.