Posted By:
cmoking"the blue background is always worth more than the pastel and the black back is always worth more than the blue black."
"scarcity dictates value, therefore the higher value indicates the rarer variation"
I disagree with the first part, but agree with the second. For example, there are far fewer Cy Young blue backs (at least per the SGC/PSA pop reports) than the black backs. Plus the blue back card has a better looking image than the black back card. The scarcity of the Young blue back dictates its higher value due to the rarer variation.