Incorrect statement in the Spatial Partition chapter

[iglind]

Adding a single object can never trigger more than one subdivision.

Imagine all your objects are in the vicinity of the top left corner of the square, and you are adding an object in the same area. This action triggers subdivision. After subdivision all objects are in one (top left) sub-square, and you have to make subdivision again. And, maybe, again, and again...

[munificent]

You're exactly right and I never considered that. I'm not actively working on the book, but if I ever get around to doing a second edition, I'll address this.