Orthogonal user experience (terminology)

I'm looking for information on the term "orthogonal user experience". I can't seem to find anything about it - be it a definition, an article, even just some sort of usage of the term.

I am following a course on security with a mixed focus on protocols and user experience. The term "orthogonal user experience" is used to refer to different implementations of the same protocol that succeed in achieving similar user experiences. E.g.: "The OAuth protocol lacks orthogonal user experience" as in "different implementations provide very different user experiences".

I am curious about both origin and reasoning as well as usage.