In my experience, referring to someone in an organization as "chief cook and bottle washer" has multiple possible meanings:
- person has a wide variety of duties in the organization
- person is very, perhaps uniquely, important to the organization in a non-obvious way
- person is almost useless to the organization
#1 seems to be the most common usage, and I'm not sure whether the others are misusages, and, if not, if #3 is ironic or just one of those weird "has two opposite meanings" things.
Also, it's unclear how to parse it. Are "chief cook" and "bottle washer" two distinct professions? If they are, is he chief cook and chief bottle washer, or is he a subordinate bottle washer? Or is "cook and bottle washer" a single profession, of which he is the organization's chief member? Each of these interpretations could imply different ultimate meanings.
And lastly, if anyone knows of an etymology, that would be great. From my failed research, it seems that it might be military in origin.