It's basically there to stop ppls with illegible names downloading, they tend to also have illegible files (japanese or other multibyte characters), I personally don't use the feature, after all Japanese users are just users like ourselves & a major contribution to the network, if they want my files & are sharing something, good luck to them, it's not their fault I can't read their language, & they certainly shouldn't be punished for my lack of ability, if I could understand it, I'd install support for it & probably download some of their files too.
