One of the Smart features of the Linestring Edit function of the latest version of Smart Edit is the dependent line editing capability.
This function can be found in the Vertical tab of the linestring edit function of Smart Edit.
For example, you started out with a Top Back of Curb Line, you joined the lines together using the Smart Edit - Join option, you elevated the line using Smart Edit - Linestring Edit - Vertical Add VPI option, and then you used Multi Offset Line to create offset lines for the Top Face of Curb, Flow Line, Lip of Curb and Edge of Pavement +/- Sidewalk lines. Each of these offset lines has a constant horizontal and vertical offset to the top back of curb line. You now realize that you need to add, change, remove or move an elevation on the top back of curb line, and that in turn means that to keep the other lines geometrically related, you have to compute the elevations for each line and add those manually also.
If you use Dependent Line editing in the Smart Edit command, you need only make the changes to the Top Back of Curb Line and the same edits will be applied automatically to the dependent lines in a single click.
Video shows you how this works