I hadn't noticed we have two related threads, so just moved this from the other one.
This is such an interesting theoretical topic. I say 'theoretical', because no ideal plan can be implemented economically. Since I only collect cards that are affordable in lower grades, this is fairly easy for me to come up with a self-serving solution:
- TPA only handles pre-wwii cards - not even cross-over employees to a subsidiary that grades modern cards. All personnel are dedicated to pre-war
- No numeric grades - just 'unaltered' or 'altered'
- Code for each alteration type detected, reference number to TPA website for details
- Published estimate of time TPA spends on each card (on average) for various value levels
- Published list of techniques used, magnification levels, etc.
- Published list of all graders and description of their expertise
The biggest problem this creates for me, as a buyer, is that graded cards are no longer commodities, so it's more difficult to determine value; however, we have that same problem with almost everything else in our hobby, especially the items with only a few known examples, and we manage to deal with it just fine.
We also have this 'problem' with all raw cards, and it doesn't seem to present the least bit of a problem for either buyer or seller.
This would create horrors only for 'lazy' or unknowledgeable sellers who would have a difficult time knowing what to pay for inventory, as they could no longer easily estimate profit. Tough luck - as a seller, I would enjoy such a problem. This is where it takes brains and knowing your product, and sellers of other items, and raw cards, have to do it all the time.