The author noted that this approach might be workable for a "real" game with smaller textures -- the biggest levels of detail for textures in the demo are 1024x1024. (And, I don't think the author mentioned this explicitly, but the demo is running in hires mode which could be dropped for a game)

His approach might be feasible with smaller textures and still represent a visual upgrade over the typical N64 "blurry mess"