Paulie rats out Tony's location to Phil (there's a precedent) to curry favor with the "new regime." But Tony knows this and sets a trap for Phil, knowing that Phil's pride will make him show up to witness the extermination Tony and his crew, thinking he has the upper hand. But the ambush will take out Phil and his entire crew leaving Tony the victor. Silvio may have had a vest on, I don't remember seeing blood. Silvio shows up for the blood bath, perhaps even giving Phil the coup de grâce right in the brainpan.
I like that idea about Dr. Melfi taking him out in the end but I just don't see it.
