Then what purpose did RMS have with the bit about publicly available specifications and being editable with generic text editors? What was he ruling out, if not things like word documents?
I think he want to rule out formats only understandable by proprietary sofwares. It seems that RMS was not really aware of the fact that word documents can be open by free software (which was maybe the case when he wrote the GFDL) (as the page http://www.gnu.org/philosophy/no-word-attachments.html suggests). But I cannot speak for him...
It just seems odd that a document translatable to a transparent copy by a free software is not itself transparent.
Olive