Surface Edits and Mid-ordinate Distance
Shows how mid-ordinate distance affects how arcs are added to a surface definition
Civil 3D Surface Breakline Edits with Mid-ordinate distance explained
Christopher Fugitt, Civil 3D Expert Elite and author of the Civil 3D Reminders blog fame, quickly explains and demos Civil 3D breakline edits.
From the Chris' YouTube Channel.
Here's the Civil 3D Reminders blog link