Edward Luttwak dissected Petraeus' doctrine at length earlier this year in Harper's. Like almost everything Luttwak writes, it's a bracingly candid and original argument - and well worth reading at this moment of non-decision. Money quote:
The essentially political advantage of the insurgents in commanding at least the silence of the local population cannot be overcome by technical means no matter how advanced. Nor can the better operational methods and tactics advocated in FM 3-24 DRAFT be of much help. So few of the insurgents ever engage in direct combat, so much of the insurgency takes covert forms, ranging from the infiltration of the government to bombings, sabotage, and assassinations, that the tactical defeats inflicted on the insurgents including the killing of their top leaders and heroeshave no perceptible impact on the volume of the violence, and of its political consequences.
Nothing will work in Iraq until there is a political settlement. And there won't be any time in the foreseeable future. The rest is futile.