If the armadillo hadn't crossed the moonlit road at that specific moment in 1967, the newlywed couple would not have died in a car crash. The 3092 search algorithm would not have substituted a perfect clone for the husband in the moment of his fiery death. He would not have been taken out of Time to be trained for a lethal mission by the last, best leader of the Terran Service. But the rule of unintended consequences governs. Cascading anomalies proliferated around that moment on the moonlit highway and the orderly flow of Time would never be the same ... if it ever was to start with.
Used availability for William R Burkett's A Footnote to History
September 2015 : USA Paperback
September 2015 : USA, Canada, UK Kindle edition