Success in the Baghdad crackdown

The Baghdad security crackdown does seem to be having some impact in the four neighborhoods targeted, although alot of that violence has simply been pushed out of those areas of Baghdad, and the regions from which the troops were pulled are experiencing heavy upticks in their violence. (Basra/Mosul, elsewhere) (It should be noted that in a recent attack, rockets were fired from one of the neighborhoods being targeted. So there still is some activity.)

The two key questions are, what happens when the US troops move on from these small successes? Will these areas stay quiet or will they return to previous levels of violence?

And, the successes in these neighborhoods are being achieved primarily by the 172nd Stryker brigades that were pulled out of Mosul and have already been extended three months. They're are exhausted and done. Will other units and configurations be able to achieve the same successes?