As it turned out, our hen Anne Elliott was not fatally egg-bound. Instead, she was suffering from a dietary deficiency -- probably calcium -- which was likely exacerbated by laying eggs all winter, while the other hens took a break. Our hen had worn herself out, and needed to recharge. Making all those eggshells had robbed her body of minerals needed for muscular control and egg-laying.
During the time that she was sick, Anne Elliott lacked the energy to terrorize her flock mates, and the balance of power shifted subtly. Anne Elliott is still the top hen, but she hasn't been bullying everyone as energetically as was her wont.
Another change that happened in the flock dynamic was the discovery of the nest boxes. In the past, there was only a single acceptable nest box, and if more than one hen needed to lay an egg, all hell broke loose. Low-ranking Lydia stopped using the boxes altogether, and moved operations to the coop floor. While Anne Elliott was sick, she camped out on the "good" nest box, forcing Harriet and Isabella to lay elsewhere. Much fussing ensued, but eventually the Knuckleheads noticed the two other nest boxes. Nest boxes that had been there all along.
Chicken epiphanies are slow in coming, as these creatures are not deep or swift thinkers.
The things we have to put up with around here. Cardigan is unimpressed.