That's very helpful information, Martin. It is really hard to determine what temperature each variety can stand in a pot.
I have always left my larger potted plants (Hardy Chicago, Peter's Honey, VdB, Osborne) out on the deck in the winter, only bringing them into the garage if the temperature falls below 24 (for us this is usually just for a few days now and then during the night hours). This has just been an arbitrary number, but I have had no die back on the deck figs. I have had some limb die back on the brown turkey in the ground on the south side of the house, none on the other in ground figs (I don't cover these at all). I have stuck most of my small ones in the crawl space this year to keep from moving them in and out of the garage, so hopefully no worries.
Can't wait for my Martin's unknown to have one of those tennis balls..