Vincent was a combination of the various Corleones, but not the way FFC envisioned.
He had Fredo's Judgment -- Banging his first cousin and botching security at the opera.
He had Michael's criminal proclivities.
And Yes, Santino's Temper.
As for cunning, I would put him below Tom Hagen.
"Io sono stanco, sono imbigliato, and I wan't everyone here to know, there ain't gonna be no trouble from me..Don Corleone..Cicc' a port!"
"I stood in the courtroom like a fool."
"I am Constanza: Lord of the idiots."
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