I've been using Outerra for several months on a daily basis, and for most of that time it has been rock solid, updating quickly even when I travel at high speed across the terrain.
Recently I started developing some bridges and houses in an area where somebody has created a lot of roads, and I've noticed that a bunch of weird things happen when the terrain has been altered with roads and memory devouring structures.
1) The screen updates very slowly, with large areas remaining low-res
2) sometimes in areas where a road has been lowered, my vehicle will rise into the air as though it is driving where the ground was before the road existed
3) Sometimes if I drive into an area that is still being drawn in low resolution, the ground will swallow my vehicle.
Am I correct in thinking that all of these symptoms come from too much infrastructure? If so, I'll just eliminate some or reduce poly count in my buildings.