His solution was rather terrible. He was using a 2.4ghz composite analog video link, the max resolution supported would have been 640x480, then stretched to the display, which itself was awful. See how it claims to be "1440 (H) x 234 (V)"? Total malarkey. That is the resolution counting each color subpixel, which nobody has done since the 90s. The actual resolution? 480x234. Over composite, with tons of video artifacts.
It is a good idea, but I never understood why bad implementation of it got so much attention on the gaming blogs. Even back then, there were much better video transmitters, much better displays, and much better tracking devices available for less than a few hundred bucks. I would understand if it was something he just threw together, but he actually tried to make this into a commercial product!
Anyhow, rant over.
That instructable you posted is a lot better done! I would not use a Gyration mouse, though, it has a lot of drift.