What is facility in technical writing?

In conventional academic writing-contexts, 'facility' in technical writing is two-fold. First, it is shown in the command that one demonstrates in the writing (an essay, article, commentary, etc.) of the technical details that have been discussed and described. Second, it is shown in the writing-style, especially by the clarity and expressiveness that are present in what has been written. Greater and lesser 'facility' is also shown in how easily one performs in both of these ways.