The FSF has a problem understanding the word "necessary".
A court will determine that any method/code/algorithm necessary to fully implement the specs is "necessary", and thus covered by MS's promise.
In contrast, MS never released the FAT family of patents under an open license, as it has with Mono. Bringing up the spectre of TomTom (in the article) is FUD -- it's irrelevant and displays a ridiculous lack of understanding of the law. (And since the FSF is a legal organization, that means their legal opinions can't be trusted to be accurate.)