Ted you're still missing the point...
A dozen Cobbs on Ebay and even the one I posted are not a total sampling of a hobby and it's cards, nor is your single collecting hsitory. Even seeing 100+ Cobb's how do you know unless you have owned them all you were not seeing the same cards repeated in your sampling. The numbers just are that, made up based on your views/experiance they are not fact and when presented as fact that's what I'm pointing out issue with.
"So, are you telling me that unless I have seen all 500 of these PIEDMONT 150 Cobb's, that I cannot make a % judgement with respect to
their centering ?"
Yes in a short you can't or should not. You can if you want but the number is nothing more than a guess. And your comment was not presented as a guess it was presented as fact. See below.
"Approximately 95 % of the Green Cobb cards that have the PIEDMONT 150 back are off-center as mine is (shown here)."
To say 95% of all P150 Cobb's are OC based on your own collecting history is not making up stories from thin air but more like pulling them from you Brown background. (Card Reference.)
Cheers,
John