This is an extremely interesting question, both from a scientific and a practical point of view, but the article doesn't really answer it at all.
He starts by measuring the temperature in the freezer, but then puts a realistic amount of food in it and doesn't want to let the food go bad. So he makes an extrapolation from the warming between -18 and -11, but immediately points out (fairly) that the extrapolation is not really valid. Then he answers a completely different question - how much cold is lost when you open the door. The answer to that is also quite dubious and of limited applicability.
The experiment I would like to see is this: fill a freezer (or a couple of different types of freezer) X% (where X could be 50, 80, 100) with a mix of different frozen foods, including ice cream, meat, vegetables, cooked meals, bread. Turn the power off. Every day, open the freezer briefly, long enough to retrieve some of your samples, maybe some from the top/front and some from the bottom/back. Then tell us, for a few types of food and location in the freezer, what day did the food thaw enough that you wouldn't want to refreeze it? What day did the food become less than perfect if consumed immediately? What day did the food become inedible?
People can put up with different levels of yickiness so you'd want descriptions more than numbers here.
He starts by measuring the temperature in the freezer, but then puts a realistic amount of food in it and doesn't want to let the food go bad. So he makes an extrapolation from the warming between -18 and -11, but immediately points out (fairly) that the extrapolation is not really valid. Then he answers a completely different question - how much cold is lost when you open the door. The answer to that is also quite dubious and of limited applicability.
The experiment I would like to see is this: fill a freezer (or a couple of different types of freezer) X% (where X could be 50, 80, 100) with a mix of different frozen foods, including ice cream, meat, vegetables, cooked meals, bread. Turn the power off. Every day, open the freezer briefly, long enough to retrieve some of your samples, maybe some from the top/front and some from the bottom/back. Then tell us, for a few types of food and location in the freezer, what day did the food thaw enough that you wouldn't want to refreeze it? What day did the food become less than perfect if consumed immediately? What day did the food become inedible?
People can put up with different levels of yickiness so you'd want descriptions more than numbers here.