Edwards' strategy for a withdrawal in the opening ten months of his administration is interesting but makes dangerous assumptions about the amount of cooperation to expect from Iraq and its neighbors. It is a strategy for dealing with the new Iraq as a serious sovereignty; whether or not it can handle the demands of sovereignty is a serious question. He has a point that more political pressure must be applied to the leaders, in essence forcing their hands to begin solving the sectarian conflict no matter how much they dislike each other.
His "slow withdrawal" would certainly provide an emphasis strong enough to make that point to people like Nouri al-Maliki. Whether or not it would extract results from the parliament is question mark at this point.
Trying to engage Iran and Syria to help in stabilization of the country is a bit idealistic; the whole of the Middle East is notoriously frugal in helping one another, generally stepping in only when their interests are threatened or there is advantage to be gained. Plus, with the level of rhetoric the US has aimed at Ahmadinejad, Iran would be reluctant partners in anything seen to have the taint of US influence; the Mullahs must keep their rhetoric vehemently anti-American for the sake of keeping up appearances. And with the US pouring funding into elements Iran has already denounced for terrorist activities inside their borders (oh the irony!) One has to wonder whether they would play nice at all...
Furthermore, the country is already feeling the pain of the Shiite-Sunni divide, and having the major Shiite neighbor trying to step in to mediate sectarian differences could very well achieve the opposite effect. At worst, you might even end up with a proxy war playing out between Iran with the Mahdi Army and Saudi Arabia with the Sunni insurgency (the Saudis already account for half of all foreign fighters captured or killed in Iraq).
And finally, Edwards' suggestion of keeping a "Quick Reaction Force" as a safety measure and to train the Iraqi army still means billions of dollars per year to keep them in Kuwait, which is really the most serious issue of the American occupation to begin with; the whole idea behind withdrawing from Iraq is to make up for the serious budgetary crisis facing the Congress and the dollar--any sort of force that is still working hand-in-hand with the Iraqis will be eating funds if it's big enough to be relatively useful in helping the Iraqis.
Ultimately, Edwards has a flawed, if interesting strategy. The Middle East has already seen that Corporate America is dictating the direction of Iraq; the idea that a new president will change this is something even many Americans would have a hard time believing. Haliburton, Blackwater, and the like need to be removed from the equation first; the military should come later.