I also kind of like old cards with markings...particularly if it looks like a kid was writing on it. Reminds me of the true origins of these cards and I like to imagine kids holding their cards, listening to their favorite players playing on the radio or reading about them in the newspaper. Very nostalgic.
But I have my limits. Here's a w517 Ruth card (not my card, image from ebay) that has kid writing, but it references 1983. Even though it appears a kid wrote on it, it's likely this card was written on during the 80's...so to me now it appears less desirable. If he had written 1933 instead of 1983, I would consider it much more desirable because I never would have known it was "modern" writing. It's funny how our mental perspective of cards can change their perceived value.
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