This is precisely why cells (alluded to in the write-up) are beneficial. If the size of a cell is bounded and you scale by adding more cells, testing the breaki

This is precisely why cells (alluded to in the write-up) are beneficial. If the size of a cell is bounded and you scale by adding more cells, testing the breaking point of the largest cell becomes an easier problem. There is still usually a layer that spans across all cell boundaries, which is what then becomes hard to test at prod scale (so you make that as simple as possible)