Green Eggs And Ham's Flesh-Kincaid Grade Level

I've mentioned readability statistics in the past, but I was rereading the Wikipedia entry on Flesh-Kincaid Readability Tests when I saw this passage:

The lowest grade level score in theory is -3.4, but, since there are no real passages that have every sentence consisting of a one-syllable word, this never occurs in practice. Green Eggs and Ham by Dr. Seuss comes close, averaging 5.7 words per sentence and 1.02 syllables per word, with a grade level of -1.3. (Most of the 812 words are monosyllabic: only one word ("anywhere"), which occurs eight times, is not.)

That's impressive. Try to write more than two good sentences with one-syllable words, and you'll see how tough it can be. Of course, Green Eggs and Ham relies on thudding repetition, but still; I was impressed.