Also, noticed something interesting while working with basements under uneven terrain. Quite often as I drag out basements that go from under one level of terrain to a lower level of terrain I have to go back to ground level and re-level out the lower level of terrain because it got pushed up by the basement tool. Another example of that golden cfe rule, Any change to one level effects every level above it.
Well, at one point the area i had to flatten out to the lower level again had a fence on it and the fence got pushed up with the terrain, of course, but when I flattened out the terrain to the lower level the fence stayed put floating above the ground.
So it seems, If you make your slope for your fence railing by pulling down the higher level than re-leveling the level will naturally raise the fence again since the fence is sitting on top of that level it can't exist below it.
But if you make your slope for the fence railing by pushing up the lower level you CAN then pull that lower level back down away from the fence without the fence budging. Since the fence is still above the level it was built on no rule of sim physics is broken by this.