Split Grading - An Idea That Would Drive Collectors Mad

Interesting
One idea is to put the split grades somewhere on the grading tab but have the overall grade of the numismatic item still in the center.
Like:
AG-3 reverse,
G-6 obverse,
But the net grade would be a G-4...
Just a thought

I believe the original ANACS Photo Certification services (while still owned by the ANA) used split grading

Correct. The American Numismatic Association Certification Service originally used split grades. My second edition of the Coin Collectors Survival Manual (published 1988) goes into detail explaining the split-grade system. They stopped split-grading in 1989 when they transitioned from soft plastic flips to rigid plastic slabs, and just before the ANA sold off ANACS in 1990.

This website shows some examples of early ANACS certificates, with split-grades: https://oldslabholders.com/anacs-ce...-generations

I think one of the key issues leading to the demise of "split grading" is how, exactly, do you determine a book value for a coin with a split grade. Grade on the lowest side? Split the difference? Be biased towards one side? There was no agreement on the issue. The book I mentioned above opines that 80% of the coin's value should rest with the obverse grade, so a coin graded MS-65/62 (with the obverse always the first number in a split-grade) would be 80% of the MS65 price, plus 20% of the MS62 price. I don't know if the TPGs today still operate on the 80:20 net grade formula.

It's all way too complicated; giving a coin a single net grade makes it much easier for investors (who were the primary beneficiaries of the early slabbing companies) to look up the value of their coins in a simple easy-to-read price guide, without needing to do maths. And trying to make a "simple price guide" for split-graded coins would have been excessively complicated, with hundreds of price entries for every single date-mintmark combination; a Redbook-equivalent "complete price guide for US coins" would need an entire bookshelf of books.