Just to give you an example, the file format tells you that there is a foot note. If the footnote doesn't fit on the page, then you have to paginate it (continue it on the next page). The file format doesn't tell you how or when to do that -- it just tells you that there is a footnote. Word happens to paginate footnotes incorrectly. Word Perfect paginates footnotes correctly. To import a Word document perfectly, somehow you have to break the pagination of the footnotes -- something that is practically impossible to do with a file importer.
Microsoft can't fix the pagination of footnotes because that's the way they've always done it. If they fixed the pagination, they would break decades of existing legal documents (which all have really long footnotes). They could add a new feature to paginate them correctly and tag them in the file format: For example "Here is a footnote. Paginate it correctly/incorrectly". I don't think they ever did that with footnotes, but they definitely did for a lot of other features (It's been over 10 years since I looked at the spec, so I can't give you a good example, unfortunately). Basically, you will see in the spec an option that says, "Render like Word 95", or something equivalent.
If you want to render Word documents perfectly (as well as your own), for each feature you need to be able to render it in your native style, and in style that Word has ever used -- even if these are fundamentally broken from a layout perspective. And then you have to add all of those Word styles to your file format, or else if you import it into your file format, you won't be able to save it.
Nobody does that, for obvious reasons. It's not Microsoft's fault. The opposite is exactly the same. That's why MS dug in their heels about not using Open Office file format -- it's an insane idea. I'm not a big fan of MS as a whole, but I interacted with the Word team a lot when I worked on conversions for Word Perfect. They were always extremely helpful -- to the point of sending me bug reports when I made a mistake on the conversions. They always knew that interoperability of their file format was only in their best interest and they did their best. Word is just a massive legacy system and they have their hands tied -- mainly because they always bend over backwards to maintain backwards compatibility for their customers.
I understand the feeling you are trying to get at, but in this case it is entirely misplaced.
