In Minnesota, I'm having more merchants threaten to take my card for just saying that. Visa seems to say you should write "See ID" and also sign it: http://usa.visa.com/merchants/risk_management/card_present.h...
So the pedantic response to your second sentence is that they consider the See ID irrelevant (and once there is a signature, it is apparently a violation of the merchant agreement to ask for ID, but I didn't look for that in the operating regulations).