About the Surface Edit Tool
You can use the Surface Edit tool to modify the surface shape in the following ways:
Edit control points
Edit knots
You can adjust the control points and knots independently of one another.
The surface that you edit does not have to be part of the current Style feature. If the surface is external, it is copied to the current Style feature, and you edit the copy. You can display a comparison between surface edits and the original surface.