I'm open to suggestions. We use this same design pattern in a the voxel system as well. The basic notion is "I need to do this operation across the tree" - the pattern is simple and repeated, so that any individual operation can be pretty simple but gets all the recursing through the tree logic without coding it.

There are some old vestiges of code that hand implemented this recursion for each operation... that's certainly not a desirable approach either. I'd say it's worse.

Is your concern that we shouldn't do things that recurse the tree? Or are you saying you'd like an easier way to implement those types of operations?