Is is possible to achieve a level of "controlled chaos" in Afghanistan, suitable for a NATO withdrawal (on par with the situation that enabled the US to leave Iraq)? Perhaps. Afghanistan does have the hallmarks of the diverse (lots of participant groups with different motivations) open source insurgency that may make a controlled chaos exit possible. For example (from Josh Partlow at the Washington Post):
The drug industry is so prevalent in places such as Helmand that coalition commanders there say it is often difficult to distinguish between Taliban members, drug traffickers and criminal gangs, all of which take part in the business.
U.N. officials estimate that the Taliban collects at least $125 million a year from opium production, including by taxing farmers and levying "protection" fees for cargo trucks transiting its territory. There are also signs that the group is increasingly involved in the high-end value aspects of the business, including converting opium to heroin and trading in precursor chemicals, such as acetic anhydride. Antonio Maria Costa, executive director of the UNODC, wrote in the report that there is "growing evidence" that "some anti-government elements in Afghanistan are turning into narco-cartels."
Note the similarities from a short description above to what the bazaar-like dynamics (the financial flows) of an open source insurgency looks like, taken from a 2004 post I made about Iraq.

A major difference between the guerrilla war we are fighting in Iraq and previous insurgencies is its lack of center of gravity as we commonly understand it (an ideology/party, ethnic independence, etc. or hierarchy). The real center of gravity in Iraq is a bazaar of violence. This bazaar is where a combination of local and global "hot" money (including criminal) is funding a diverse set of groups, each with their own methods of operation and motivations. Groups engage in co-opetition to share resources, intelligence, and funds (see the attached simplified diagram). They even expand operational reach by purchasing amateur mercenaries (not pictured).
It's pretty clear that US commanders on the ground already see the free-wheeling financial bazaar that super-charges Afghanistan's open source insurgency as central to the war (again, from the
Josh Partlow article in the Washington Post):
Col. George Amland, deputy commander of the 2nd Marine Expeditionary Brigade, which operates in Helmand, said that "all those people will coexist very happily as a partnership, while there is a level of chaos," but that his troops are attempting to interrupt and split the networks.
However, what the Col. will find is that forcibly interrupting or splitting these networks won't work. To create a level of controlled chaos necessary for withdrawal, it's necessary to:
create your own open source counter-insurgency by co-opting existing insurgents (purchasing them) and manufacturing "loyalist" militias.
The creation of an open source counter-insurgency is the strategy I outlined in my 2005 New York Times Op-Ed, "The Open-Source War" on how to solve the problem of Iraq. That strategy, made easy by deep fault lines that developed due to a growing Iraqi civil war, eventually became (inevitably) the strategy the US used to put Iraq into a mode of "controlled chaos." From the Op-Ed:
What's left (as a strategy)? It's possible, as Microsoft has found, that there is no good monopolistic solution to a mature open-source effort. In that case, the United States might be better off adopting I.B.M.'s embrace of open source. This solution would require renouncing the state's monopoly on violence by using militias as a counterinsurgency. This is similar to the strategy used to halt the insurgencies in El Salvador in the 1980's and Colombia in the 1990's. In those cases, these militias used local knowledge, unconstrained tactics and high levels of motivation to defeat insurgents (this is in contrast to the ineffectiveness of Iraq's paycheck military). This option will probably work in Iraq too.
So, when will it be apparent the US is starting to adopt an open source counter-insurgency as its exit strategy? When it starts to manufacture, co-opt and run its own "loyalist" militias, apart from the Afghan government. So, why don't we just jump to the end game early?
NOTE: However, when we do eventually adopt this strategy (sooner or later), it's important to remember it comes at a cost (again from the 2005 Op-Ed on Iraq):
If an open-source counterinsurgency is the only strategic option left, it is a depressing one. The militias will probably create a situation of controlled chaos that will allow the administration to claim victory and exit the country. They will, however, exact a horrible toll on Iraq and may persist for decades. This is a far cry from spreading democracy in the Middle East.