Sharing an electric blanket and other challenges

I happen to have a lot of experience with electric blankets. It comes from owning that old unheated New Hampshire summer getaway I've mentioned earlier, and from making an occasional winter foray into it on snowshoes to see if it's still standing and to retrieve one or another forgotten item. The best way to survive the night there in freezing conditions (both inside and out) is to turn on an electric blanket several hours before getting into the bed and letting things warm up a bit. But invariably, when you get into the bed and lie there for a while, you find that some adjustment of the temperature control is needed. If it's too high, you wake up sweating to death, and if it's not high enough, you wake up wondering why you decided to torture yourself by staying overnight. With adjustments during a single night or a setting based on experience gained over several years, it's not too hard to find a “stable equilibrium setting that keeps things at or close to a comfortable, constant temperature. Fine so far.

The situation is slightly more complicated when my wife accompanies me as we prefer somewhat different temperature settings for the blanket. Thus there have been occasional middle-of-the-night adjustments by one or the other of us to suit our own tastes, hoping that the other person is sufficiently sound asleep not to notice.