That is a good point. The "ordinal" century doesn't exactly line up with the digits in a "YYYY" format, thus "CCYY" creates some ambiguity depending on how one

That is a good point. The "ordinal" century doesn't exactly line up with the digits in a "YYYY" format, thus "CCYY" creates some ambiguity depending on how one defines "century". I conclude my fanciness of using "CCYY" is not useful. :)