Cuts from the speaker to some background footage, then back to the speaker, are a very useful technique. They can be used to lie, too, of course (cut from the interviewee's face to the interviewer, then back to the interviewee, and you can cut out context that changes the meaning of what was said). But when used with no deception in mind, they can really enhance a powerful moment. And this was a perfect example of it: no deception at all, just a wonderful visual image that makes an impact on the viewer.