One of the bok choy plants finally did make it into the kitchen.
I don't know what it is about bok choy, but I always cut the whole plant to bring in, whereas for most other greens I tend to just bring in the leaves that I will need for the meal I have in mind. It could be the thickness/succulence of the petioles that causes me to reach right past them, to the base of the plant.
There are still three bok choy plants out in the yard, and I may experiment with one of them, cutting off just the leaves I need, to see how that goes. Does anyone else harvest bok choy one leaf at a time?