> What the actual hell? You can sign up online to get mail scanned… without any physical verification you're at the address, with only a physical notification being sent after-the-fact?

I signed up for Informed Delivery a couple weeks ago, and it did ask for additional verification information. It was similar to questions asked by financial institutions when opening accounts online: "which of these 4 addresses have you lived at in the past?", "What was the name of your first pet?", etc. All presumably information that has been collected by companies such as Experian.