A key word with regard to a sub-corpus is a word of which the frequency in that sub-corpus is significantly higher than expected under the hypothesis that its use and the variable “part of the corpus” are mutually independent. A study in literary statistics almost invariably includes a chapter devoted to key words. However, a strong attack has been recently launched upon the way stylometry has been modelling texts since the classical works of Herdan, Guiraud or Muller. In fact statistical modelling seems as valid in stylistics as in any other field of the humanities and social sciences. What is questionable is the fact that many studies in literary statistics are more satisfied with the easy identification of monsters, i.e. literary phenomena unexplained by wrong models, than with the laborious research of models fitting the textual data well. A short examination of the mentioned controversy and the quantitative analysis of an example provided by Laclos' novelLes Liaisons dangereuses endeavour to support this argument.