I'm not convinced. Michael is carry out his more sanguine solution to things by turning their execution over to Vincent. But, just as Vito planned much of the '55 massacre, Michael has his hands and mind in the GFIII massacre. Also, reagrdless of one's motivation, a transgression of the law (or morality) is still that, a transgression.

So, while he no doubt wanted out, he did not completely sever his relationship with what he wanted out of until it cost him the ultimate - the death of his daughter.