Author Existence Failure: Sadly, Dickson died in 2001 and never got to finish the Cycle, or the trilogy focusing on Bleys Ahrens.
Defictionalization: The Dorsai Irregulars, a fan group created to provide security for science fiction conventions.
Schedule Slip: Twice. Dickson had a eight year break between Tactics of Mistake and "The Spirit of Dorsai". After Other was written in 1994, he didn't even finish Antagonist when he died in 2001.
What Could Have Been: The Childe Cycle was a rather ambitious undertaking. Not only there were six sf novels, but also three planned historical novels and three novels set in the present. Sadly, with Dickson's passing, we'll probably never get to see the full picture.
Word of Saint Paul: David W. Wixon, Dickson's long-time assistant. He complied "The New Dorsai Companion", and finished Dickson's last unfinished novel Antagonist.