New language fluency test

Shannon tested and found the "the enormous implicit [...] statistical knowledge of" the English language most people have.  His measure, predictability of the next letter given the previous 100 letters seems like a universal, simple, and objective measure of how well one knows a language not specifically dependent of spelling rules, vocabulary, grammar, understanding, and idioms.  It could be used to measure fluency in place of ESL tests, and I probably will use it when learning foreign languages to measure improvement, etc. from now on.  Probably should be used to represent the difficulty of languages as well.