I found that article while trying to research what I really wanted to request, a way to convert thick, dark body hair to light, translucent peach-fuzz.
I remember reading an article years ago that described a theoretical mechanism that could achieve terminal to vellus hair conversion, but now I can’t find it. Still, I think it’d make an amazing field, if a mechanism can be found, to convert all body hair below the throat from terminal hair (thick body hair) to vellus hair (peach-fuzz).