Originally Posted by kovidgoyal
Actually, now that I think about it, why is that impossible? An open DRM scheme is easier to crack, but closing the DRM doesn't really guarantee it wont be cracked. The only real defence DRM has against being cracked is a legal one. For example, MOBI DRM is trivial to crack if you have the PIN used to encrypt the file, and not so trivial if you don't. In fact, MOBI DRM is a de-facto open DRM scheme.
Perhaps you're right. My thinking is that the purpose of DRM is to allow rights-holders to control how digital content is used. A particular DRM scheme only achieves that end if every piece of software able to access so-controlled content respects the restrictions the rights-holders place on the content. Truly open DRM necessarily means anyone can produce software which accesses the controlled content without restriction, defeating the whole purpose. If you define the purpose of DRM as something weaker, like "reduce the number of end users copying around content willy-nilly," sure -- then an open DRM scheme could work. My intuition however is that most DRM advocates are thinking of something closer to the former definition.