Another (perhaps parallel) possibility: By using an outside bodyguard, Michael was signaling Roth that he didn't trust (or hadn't ruled out) Neri and Rocco, and was still looking inward (inside his family) rather than outward (toward Roth).
Ntra la porta tua lu sangu � sparsu, E nun me mporta si ce muoru accisu... E s'iddu muoru e vaju mparadisu Si nun ce truovo a ttia, mancu ce trasu.
