On the other hand, designers do make mistakes. It's so easy, when you know how to get there, to think that you've given someone else the right road directions.
Turns out Eight Godmothers did have a flaw in the pattern. It should have been CO25, and the last yarn-over on the increasing rows should not have had a compensating k2tog. With that change, the BO4 makes sense, because you're then back at 25sts. (If you're not a knitter, this will sound like pure gobbledygook.)
More than one sweet lady tried to nudge me toward that realization . . . not with an accusation, but with a very gracious question. And so this morning I am appreciating the sisterhood of civility, the kindness of gentle natures. In a world of road rage and political invective, the sweet and sincere question is a balm to the spirit. Courtesy is not dead; it lives on Ravelry.
The amended pattern is up.