Photo-Matching

[Jim65]

If you're talking about taking a common game used jersey and turning it into a HOF worn, a forger would have to take a jersey completely apart to make seams match, remove all set strips, numbers, lettering, embroidered player names, etc. It would be extremely difficult to do without leaving evidence like extra needle holes, differing colors on jersey, different threads and stitches, etc.

To me, its possible but there would always be some evidence there if you look hard enough.

I definitely agree with your point about negative test. I've seen way too many people call a loose thread a photo match. People look for 1 similarity rather than looking for a difference.