Actually, I left the art and artifacts authentication area a while ago-- work in cognitive science now--, am not an active collector, but the current issue has intrigued me.
I've decided to look into scientific ways to identify and scientifically document alterations, including full spectrum light scans to identify many alterations of cards already in holders (as removing the card from a holder is an issue, including concerning voiding the guarantee). I have an idea for the firsts tests, and I'll consider this my pet project.
I don't plan on "starting a company"-- that always seems to be an angle in this hobby--, but, I hope, have techniques that can be used by others to assess cards-- I hope including while they are still in holders. It would be great if there are methods for collectors to examine their own holder cards, and, of course and even better, raw cards, and methods to test the accuracy and quality control of graders.
I also thing advanced scanning systems (not using normal visible light) will not only do well at identifying alterations, but can create images that can be used for others to example, show that the card has been examined thusly, and help document for posterity the card. I tend to see advanced scanning as the wave of the future, and, as the cards has been scanned and the scans readily available, the cards won't even have to be professionally holdered. In art and artifacts, and elsewhere, advanced imaging has been used as security 'marking,' akin to DNA marking.
Further, authentication of cards can be done via looking at really good scans (magnified, large), which means people can have the image of their card scanned then send the images rather than the card itself for authentication. People sometimes send me microscopic images via email so I can identify the printing, etc. And, also, an image is availble for many people in different places to examine-- including of grade.
But I'll start by seeing what alterations can be identified-- as documented as evidence-- using my test systems.
Authenticating Art and Artifacts: An Introduction to Methods