A quick poke at dictionary.com, following "competency" to "competence", reveals this definition:
1. the quality of being competent; adequacy; possession of required skill, knowledge, qualification, or capacity: He hired her because of her competence as an accountant.This in my opinion could be read to support either the minimal or maximal position. So it all comes down to connotation. And since fjm and goulo are from opposite sides of the Atlantic (though both reside on the eastern shore now), I can't blame it on the Anglo-American language divide.
2. sufficiency; a sufficient quantity.
When discussing writing, does "competency" imply minimal acceptable quality or maximal desired quality?
Minimal acceptable quality
Maximal desired quality
Some intermediate state
Something else I'll explain in comments