Do you remember, some years ago, some people had a habit of using “literally” not in the dictionary sense, but for emphasis, as in “The boss is literally breathing down my neck”? In recent months, I’ve noticed people using “sort of” and “kind of” not to mean “more or less” or “in a way”, but for punctuation, emphasis, or decoration.
A lot of times, adding “kind of” doesn’t change much (“we need to kind of speak up about this”), and so it is merely useless. At best, it means “the following isn’t exactly what I mean, but it’s close, and I want to move on, rather than waste time finding the correct word.”
I think for Mr. Mattis it’s slightly personal, which is he wants to come back and make sure that he’s connected over here and provides the best kind of advice on what to do forward.
Which immediately raised the question, “What kind of advice is the best kind?”
I’d like to appropriate a piece of advice often attributed to Mark Twain: instead of saying “kind of”, say “fucking”, your editor will delete it and your sentence will be as it should be. Except that people don’t employ editors in casual speech, so maybe autocorrect can be modded to do this.