I said that badly. What I meant was that ASCII 0x2d is, in fact, used as the only minus sign in basically all markup and presentation layers. (Mostly because math layout tends to go through its own interpreter -- what lives in "the unicode text" is always "markup" of some kind). The unicode value is ignored AFAIK, nothing emits it or interprets it specially. That is not true of the hyphen, which does get special treatment at the presentation layer in fonts and whatnot.