It would be so much less overhead to require adult sites and user content driven sites to simply add the RTA adult header and put the responsibility on parents

It would be so much less overhead to require adult sites and user content driven sites to simply add the RTA adult header and put the responsibility on parents to use parental control software. It looks like this: rating RTA-5042-1996-1400-1577-RTA and it can be sent via http headers, or embeded in web pages. Requiring people to register with PII is just asking for trouble.