What is a Shaggy Dog Story?

You ask, "What is a shaggy dog story?" and this brings to mind the years I spent as a janitor in a pickle factory. These were extraordinary pickles, the world's largest, cultivated in vats the size of zeppellin sheds and salted by cascades of water the size of Niagara, drawn from the nearby sea. As you can imagine, the combination of salt and pickle matter led to some challenging clean-ups, and in this I was aided by a series of books written by Marceau de Savon, famed cleanser to royalty and hygiene-advisor to the stars. The books were first-rate, as all the reviews testified (even Gore Vidal was impressed), but their great limitation became evident when I failed to discover the word "pickle" in the index. To make a long story short, I was forced to improvise, and eventually learned that the best way to clean up the residue of a pickle factory was to use the leftover dough from the hamburger bun factory next door. But to answer your question --  I've no idea.