Legend label different from map label without manual modification

[PeterSanderson]

Create a way to have the legend label be based on a different attribute than the symbology attribute(s).  The key here is automation.  I know that this can be done manually with Symbology -> Categories -> Unique values, many fields; but if I have hundreds or thousands of records, it becomes a daunting task.  Maybe this could be added to the advanced symbology menu where you find "symbol levels"?

Example:  I have a trail map for a park showing different trails, each has a trail color and a trail name.  I have an attribute field for "Trail Color" for use with symbology (e.g. "Red" gets the typical red trail symbology).  However, I do not want to legend to display "Red" as the description; I would like it to draw from a different attribute field called "Trail Name".  This would allow me to easily symbolize the map based on the color attribute and have the legend display the trail's name (e.g. Prairie Loop) based on a different attribute.