If you aren't playing Wisher, Theurgist, Fatalist, then you have no legitimate need for the rules of Wisher, Theurgist, Fatalist (WTF 45)
But character generation is done before one begins play (WTF 62)
And the character generation procedures for an RPG are commonly understood as part of the game rules [citation needed]
These three premises add up to a contradiction, where the only two escapes are by asserting that WTF's character creation procedures are not, in fact, rules of WTF but instead something else, perhaps setting elements or norms of play culture, or by coming to the conclusion that it is not possible to legitimately create a WTF character.
a more pressing question is whether you were playing WTF when you wrote this post and if not what the heck you thought you were doing using its rules
That's unknowable without a Wisher involved.
Also making this post was not needful. So legitimate or not, I didn't have need of the WTF rules because I didn't need to make the post.
I'm also not entirely convinced that examining the structure of something qualifies as using it.
I'm also not entirely convinced that examining the structure of something qualifies as using it.
More seriously, to address the original claim, legitimacy does not derive from the text of a roleplaying game but rather from the will of the people. It cannot derive from text because nobody can know what a text actually says.
Are you intending to imply that "the will of the people" is itself legible? If so, how? To whom? Via what method?
probably the simplest way is a Knowledge + People roll, but one could also look for which character creation efforts are legitimate and work backwards
