What exactly did Leto plan for Duncan Idaho? Did he know Duncan would be able to regain ALL of his lives' memories?
Obviously, Leto used Duncan heavily in his breeding program. Despite Duncan's prostestations that he would not be Leto's "damned stud," he did in fact participate many times.
It has been suggested here that Leto merely used Duncan, an "older model," as a control and a dampener against the KH gene. Surely there was more?
What is Duncan best known for in combat? His improvisation. Why, of all the Duncans, did Leto approve of the one who helped kill him the most?
Because that Duncan surprised him:
1. Stripping off his uniform when Leto's entourage was attacked by Face Dancers under the guise of Duncan.
2. Duncan's lament about the "magic" Leto has stolen from the Duncans by taking them out of their natural era.
3. The Duncan of GEoD disobeyed Leto re: Hwi, although perhaps this was predictable, it was out of character.
4. Not sure quite how or why, but this particular Duncan inspired Moneo to try to save his life when he never had before.
One of my favorite parts of the entire series is Leto's audience with the Rev. Mothers Lukeysal and Anteac. ("Waste not, want not" makes me LOL every time I read it.) When Duncan interrupts at the end, Leto gives precise detail on how to defend/attack, and Duncan wonders why Leto even needs him.
With the presence of the Bene Gesserit, Leto cannot serve up his usual line of BS about the Paul/Leto I within desiring his companionship.
"M'lord, why do you need me?" Idaho asked.
"For your strength and loyalty.
Idaho shook his head. "But..."
"You obey," Leto said, and he noted the way these words were being absorbed by the Reverend Mothers. Truth, only truth, for they are Truthsayers.
Maybe I am making too much of this, but to me it suggests that Leto had ulterior motives he did not want revealed to the Bene Gesserits (or his journals!) and that he placed GREAT importance on the serial reincarnations of Duncan.
What is the ultimate result of the Duncan-Siona line? There are many, many humans who can elude the prescience of Navigators, yes. But the payoff is in Teg Miles, in Sheeana.
Always does the unexpected.
The Bene Gesserit with the artist's soul, the Dune waif who dances the language of Siaynoq/the Divided God, who will create the new.
more thoughts later...