Vito never would have approved of the hit. And if Michael had done it without his knowledge, he would have been heartbroken. He would have blamed himself because, as he said in the garden scene, "I never wanted this for you, Michael..."

The logical part of Vito might have agreed that a traitor should never get a pass. But the fathter part of Vito would never have approved of a brother killing a brother for any reason. He would have concluded that the fraticide was an inevitable outgrowth of his own life of crime.