From a reader:
“Darth” is used the same way as “Kennedy.” If you are associated with the dark side, you work either Darth or Kennedy into your name as the occasion fits, i.e. Jacqueline Kennedy Onassis, William Kennedy Smith, Kennedy the MTV video jockey, etc.
P.S. If the Trek-O-Meter hits it mark I’d like to see some Trouble with DERBbles merchandise.