I was going to gut my plaster walls and drywall over it because it's pretty beat up and there seems to be a slight slope going out towards the nose of the highest subway, about shoulder height.
But my wise dad says that because it's so consistent all around maybe that was part of the old design. It's all solid, not crumbly.
So because of this and that this old plaster is irreplaceable in it's fortitude, I've decided to knock out and skim and make it nice again.
Anyone ever heard of this characteristic?