[drcy]

No insight on the Fitzgerald connection, but, with a microscope, you can identify stamps made from the same rubber stamp. And ones made later from a different rubber stamp. All printing plates, including rubber stamps, have identifying microscopic 'fingerprints'-- unique microscopic imperfections, marks, shapes, etc. It's a standard forensic technique to match prints from the same printing plates. It's how they proved a letter came from a specific typewriter in the old day mysteries.

Chances are you don't even need a microscope to identify a new F stamp. Just a close look.

But I agree that demonstrating that an 'F' stamp has been around for a while is the simplest way to establish the 'F' stamp is one of the originals. Being able to establish that something has been around for a while (a form of provenance) is usually a good thing these days. One use I see for getting a card graded.

And, as mrvister accurately says, you want to document the existence of your F stamps before a flood of forged stamps come out, not after. It can be as simple as posting a photo to photobucket this afternoon.