Yes, Montanari wrote an entire book on this one little proverb, albeit a little book of 88 pages (excluding references.) The very fact that a scholar and specialist is writing an entire book to explain the meaning of a proverb (and a well-known one at that) from his own culture is already odd. Odd because proverbs are undeniably an expression of the popular voice. And this is where my reasoning differs from Montanari's. He maintains that the proverb was an injunction by the upper classes to disallow the pairing of upper-class pears and lower-class cheese, a sort of propaganda for class privilege and stratification.
Proverbs are obviously a part of the oral tradition, and the upper classes propagated their knowledge by the written, not the oral, form. Literacy was rare and discouraged for this very reason. An exception may be the Bible, whose maxims became popular, but were originally passed on in an unwritten manner by literate priests in their (oral) homilies, or visually through paintings, or by plays.
To illustrate his point that proverbs can come from authorities and not the popular voice, the author asks rhetorically, "is 'one swallow does not make a summer' not perhaps a quotation from Aristotle?" But wait a second: the fact that the saying is found in Aristotle (Nicomachean Ethics) does not prove that it is a quotation from Aristotle; it is more likely that Aristotle was quoting a proverb to prove his point, and as everyone knows, a proverb needs no attribution. The translation has quotation marks, but the original Greek would not have quotation marks (they did not exist in ancient Greek). Does Montanari seriously think that this saying came down through more than two millennia because people in different cultures were reading the Nicomachean Ethics?
So, the proverb remains an enigma. And the biggest enigma is how a saying people don't really understand anymore continues to be known and repeated. As the tradition of proverbs is an oral tradition (with some written compilations, of course) it will be difficult to understand how this happened.
(In the photo, Seckel pears. I had a delicious Seckel pear and cheese pastry at this weekend's Boston Local Food festival- I wonder what would have happened if I had quoted the saying to some of the farmers...)