Soaking the joints in oil sounds, initially, to be an idea with some merit. One method of finishing furniture is to hand rub the article with linseed oil. This is a slow process, consisting of rubbing the oil into the wood a little at a time and allowing it to dry between applications. Although this process is time consuming, labor intensive, and not cost effective for the manufacturer, it does seal the wood. One can apply the same methods to oiling the bore of a clarinet as one does to finishing furniture.
Linseed oil is a little thick and needs to be thinned with turpentine.
Turpentine is not really something you or the rest of the orchestra wants to breath while playing a Beethoven Symphony. However, Mineral Spirits is a petroleum product. Dependent upon conditions, a clarinet should be sealed once a year. The effect on the key-work is also evident. Persons with acid hands should wipe the exterior of the instrument with a soft cloth after each use and seal it every 6 months.