That's a really useful trick!

[No matter what was being visualized, being able to do it in the first place is still cool.

And he doesn't go quiiite that fast, though it's a deliberate effort after the first minute or so.]

Would it work if you were just looking at pictures of them, or do you have to 'meet' them in person?

[Something about the phrasing strikes him as odd - a little anthropomorphic, perhaps?]