Al contadino non far sapere quanto è buono il cacio con le pere

Keep someone (in this case a poor farmer) in the dark about a secret that could somehow, if revealed, come back to haunt those who have not been able to preserve it. Basically… the farmers produced both pears and cheese. If they had known how good this pairing was, they would have ended up giving the bottom of all the pears and all the cheese, to the detriment of the owners’ tables, who instead… knew… but remained silent… damn!
Although I have a doubt… what if it is ironic? What if the farmers had always known? Who more than them knows the secrets of good food?