"If you're too often other people, you'd just be a blur, a mish-mash of shifting parts." In his experience, the best way to pull on another person's identity is to know yourself well and work from here. "When I was younger, I had some practice keeping out unwanted psychic visitors and for all the useful skills I don't remember, it seems that one has stayed with me."

When he mentions his youth, there's a brief impression of a younger man: whippet thin from exercise and not eating well, wearing an outfit that is a cross between wizarding robes and muggle clothing. The clothing is neat and relatively clean, but shows signs of long-term wear and repair. The robes have a couple of singe marks, but the damage doesn't extend to the charmed embroidery around the edges. (How could Mycroft know for sure that the stitching is magical? Dream logic, that's how.) Peeking out from under the robe, a young Harry is wearing a customized holster that carries both a handgun and a wand and shows regular use.