A Linguistic Fingerprint?

I stumbled across a BBC article about research into a method to linguistically fingerprint an author. This work has found that a "curve" based on the number of words an author uses only once and the length of the work seems to be a reliable method for unique identification of the writer. So, I find this concept very interesting. Apparently a great deal of analysis and testing has be performed by applying it to the writing of great authors like Herman Melville, Thomas Hardy, and D. H. Lawrence. I can't help but wonder, however, if it breaks down for a hillbilly like me. I don't think my vocabulary is big enough to house "unique words." Just a thought from this Blind Bambi.