That’s my understanding of things as well. Big concentrations of troops become vulnerable and easy to track. The approach of creating a broad front is the obvious alternative. Ultimately, Russia’s goal is attrition, but splitting the front would also be very valuable. Seems like after the collapse of Avdeevka, there’s nowhere to fall back to, so Russia could end up pushing all the way to Dnepr, an then Ukraine will lose all communication between the north and the south.