the presentation setup here is fantastic. it took me a second to realize how it works: the video and the logo on his shirt are both horizontally flipped. idk if this is a common thing or not but it makes for a very effective and natural presentation.
I guess the flipped T-shirt is just for showing off (and nerd-sniping). It would work just as well if the T-shirt didn't have an image on it (negating the need for printing a custom T-shirt).