The problem is, nobody _implements_ ID3v2 correctly, so you never hear about these tags being used.

It would probably be more accurate to say that nobody completely implements all of the ID3v2 spec.

ID3v2 is such an all-encompassing spec that it's unlikely that anyone would ever implement it fully. Fortunately, it's designed so that it can be only partially implemented if the developer so desires. Such a partial implementation isn't incorrect, it's just less than complete.

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Tony Fabris