I don't agree with any of you on this Neri/Rocco thing. Neri was Michael's Luca, recruited specifically by Michael (with Vito's help) to serve as his bodyguard and do his bidding otherwise. He was a special who was salaried as opposed to given a source of income. Rocco was set up as a capo with a regime as soon as Michael's plan for revenge began to coalesce. From all evidence, Neri remained as Michael's confidant and Rocco as a capo. I don't interpret anything in the film as indicating a rivalry or contest for ascendency or Michael's attention.

"Generosity. That was my first mistake."
"Experience must be our only guide; reason may mislead us."
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