It doesn't add much value.
But it does show a start of something different. (For what reason ever: divider between main and other cast, ...?)

Personnaly I wouldn't enter. But some of us users like to copy exactly what's on screen. And on cast I can figure out more reasons than on crew.

My opinion, for what it's worth..


Group dividers in crew to show in credit company listing
    VXF Company
      VFX Supervisor
  etc

Divide up multi crew credits into separate entries
  Writers
      A
      b
to be

Written by A
Written by B



Group Dividers within crew credits, to show approved groupings, within the limits of the program.  I do not like blank dividers, I don't think they add anything to the cast list. 

I would like 1 alteration to the group rule.
  If the cast list ends with a "grouping", add an "End Group" marker.  Just in case somebody come along to add uncredited creds.


That was worth about $0.0125 based upon the current exchange rates