Yes, Doug Hillary wrote an excellent article on the utility of Used Oil Analysis that is featured on the main page of the site:
UOAs are a great tool in the Management of any machinery that uses liquid lubricants. Unfortunately, their real value is often misunderstood by those who contribute to BITOG. Firstly, it is important to realize that you get what you pay for. The most common forms of UOA are limited in their...bobistheoilguy.com
Is he still around here?