a cardinal rule for research?

I've started to dance with the devil (wrestle with research) again, at least in a more meaningful way than the previous flirting allowed by my restrictive schedule. One of the first things I've realized is that I have made assumptions about what constitutes the parameters of a definition of academic librarian competency. Why? Or perhaps, how did I come to this conclusion? I forgot something I should perhaps consider a cardinal rule: sometimes what isn't there is more revealing than what is present. Competency is defined in much of the literature as knowledge or education, skills and experience or ability. Not all authors provide definitions that include all these aspects, whether on purpose or by chance. What does this say about the authors who don't provide definitions, or provide "partial" definitions, assuming the presence of all three facets is the most common definition? And what about those who don't formulate competency using these facets and/or use a completely different approach I haven't yet comprehended? I don't know but at least I have realized I need to expand my initial search set (the results used in my first article on this topic) to incorporate any article from my initial literature search that doesn't assume competency (and luckily, there aren't many).