I don't think some small engines are designed to operate while tilted to one side or the other. Maybe one of our mechanics will comment?
I use my DR All Terrain mower as straight up and down slopes as I can. It has a lockable differential. No problem mowing the pond bank as long as it is dry. Probably most pond banks only need mowing every couple of months in the growing season. Grass is good; woody brush is not.
