[zmmmmm]

Yes, to be clear, (and I realize now that I wasn't above), what I'm talking about above is what a patent examiner is allowed to use to routinely disqualify a patent up front as part of the application process prior to granting it.

The examiner is not allowed to go on research expeditions to interview witnesses, or to locate, purchase and reverse engineer old products to prove they are implemented in such a way as to invalidate the patent. A court (or the litigants) can certainly do all that, but here we are focusing on what can invalidate a patent prior to it being granted. And for that we are limited to certain classes of readily verifiable types of evidence.