Reality strikes
If you've ever subscribed to the Microsoft Developer Network, or MSDN as it's commonly known, then you'll find the OOXML "standard" document familiar. It's a typical example of Microsoft MSDN-style technical documentation. It isn't badly written; indeed for proprietary documentation it's about as good as it gets, but as I've said before of Microsoft documentation, it's fuzzy on the details. It's not a standards document, something you can use to unambiguously create an implementation from scratch.
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A good example to use to compare it to real standards documents is to examine Internet Engineering Task Force (IETF) "Requests for Comments" (RFC's) documents, which are publicly available on the Web. They use key words such as "MUST", "REQUIRED", "SHALL", "SHOULD", "MAY" and "OPTIONAL" and these words have real meaning in the standard, such that an implementor can be guided by these terms. The OOXML spec just doesn't use the same precision in language that a real specification needs. It was almost certainly written by documentation professionals, not by engineers who actually understand the needs of the implementors of a standard.
OOXML is too hard to implement … even for Microsoft
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So various things could be true here:
* Microsoft is not putting proper resources behind maintenance of Office 2004 for the Macintosh. * The software engineers working on Office 2004 for the Macintosh aren’t very good. * OOXML at 6000+ pages is just too hard a specification for expert software engineers working closely with the people who designed OOXML to be implemented easily and completely.