What is an Ennetree?

What if you took a quadtree, but instead of dividing space with a binary-split on each axis, instead used a trinary-split. This would result in the space getting subdivided nine times instead of four. But interesting, the "center" subdivided area would be "stable", unlike the quadtree subdivision approach. Are there situations/use-cases where this would be useful? I don't know!!

I've made a repository with both a quadtree and what i'm calling the 3×3 variant an ennetree (or nonatree). Some basic benchmarks do in fact show that there are some use-cases where an ennetree out-performs a quadtree.