Is it possible to modify a polygon anywhere other than at the corner vertices?

The statement in the answer focuses on the properties of polygon editing in GIS software such as ArcGIS Pro. In traditional polygon editing, modifications are typically confined to the corner vertices, or vertex points, that define the shape and boundaries of the polygon. This is because polygons are constructed as a series of connected line segments that form a closed shape, with vertices marking change points in direction.

Modifying a polygon by adjusting only the corner vertices maintains the integrity of the polygon's definition. While advanced tools and options, such as reshaping or smoothing polygons, may allow for more complex modifications, they still fundamentally operate by influencing the vertices that define the original shape.

Options suggesting the ability to modify polygons in ways not focused on corner vertices would involve methods that could compromise the polygon's geometry or lead to distortion. Therefore, the modification of polygons can only occur legitimately through the manipulation of the corner vertices, aligning with the standard structure of polygon geometry in GIS applications.