The back of my card (I only have one) says “See ID.” Mostly, nobody looks at it anyway. The ones who do cheerfully ask for an ID, which I usually have out already. I’ve only once had a clerk insist I sign. I didn’t and I never went back to that store again.
Did you read C (which you conveniently snipped out)? I’m pretty sure that notice of potential liability is given in the cardholder agreement concerning the prompt signing of cards upon receipt, but I’ll have to look into that.
“C” does not negate the other provisions, namely limitation of liability to $50, etc. If no notice is given as to potential liability, the cardholder has no liability whatsoever.
I use a fine-point indelible marker – in my experience, that will last for the life of the card.