One doesn't have to like nor agree to negotiate with the disparate elements of the Taliban, but one should at the very least understand who they are speaking about when referencing the Taliban.
The Taliban is not a monolithic entity. Today's 'Taliban' is comprised of various groups, each with varying degrees of fundamentalism, economic desires and above all, nationalism. The binding goal between all groups is the desire to rid Afghanistan of Western presence. But those groups are favor nationalism over fundamentalism can and should be approached. Guarantees of a seat at the table or government and the promise of a NATO withdrawal can entice then to unite and reach compromise with the parties currently in Kabul. The entities that favor nationalism, by and large, will not wish for an trans-national terror group infringing or compromising their newly bequeathed sovereignty.
The former 'Taliban' regime [Mullah Omar's boys] is now known as the Islamic Emirate of Afghanistan. The IEA enjoys control over large swaths of Afghanistan. They are not included in what could be termed moderate elements of the Taliban. Many of the foot soldiers and low level functionaries of the former regime have, after 2001, melted into the countryside, watching and waiting to see who comes out on top. Lately, that has been the the 'Taliban'. In order to gain support in their struggle, even the radical arms of the 'Taliban' have moderated their ideology. In 2007, Mullah Omar declared that music and parties were now permissible. Insignificant to us, but a cultural long jump for these Muslims. Whether or not that would continue under a renewed Taliban regime would be anyone's guess however.
Several insurgent groups and warlords have been misnomered by politicians, pundits and debaters as 'Taliban'. But many of these groups are ripe for approach in a regional, comprehensive strategy to restore stability to, and to withdraw from Afghanistan. Hizb-i-Islami is such a group, headed by Gulbuddin Hekmatyar, and staffed by university educated Afghan's and once a Mujaheddin ally of the CIA.
Mawlawi Jalaluddin Haqqani heads yet another Mujaheddin group [this one aided by Pakistan's ISI], and was once invited by Hamid Karzai to be the Afghani Prime Minister. The Tehrik-e-Taliban Pakistan is based in Waziristan, fights against the Pakistani Army, but has heard entreaties by Afghan and US sources.
Even pro-war hawk and armchair commando Frederick Kagan maintains the need for understanding, and negotiating with the nationalist arms of the 'Taliban' umbrella.
There is no such thing as "the Taliban" today. Many different groups with different leaders and aims call themselves "Taliban," and many more are called "Taliban" by their enemies. In addition to Mullah Omar's Taliban based in Pakistan and indigenous Taliban forces in Afghanistan, there is an indigenous Pakistani Taliban controlled by Baitullah Mehsud (this group is thought to have been responsible for assassinating Benazir Bhutto). Both are linked with al-Qaeda, and both are dangerous and determined. In other areas, however, "Taliban" groups are primarily disaffected tribesmen who find it more convenient to get help from the Taliban than from other sources.
In general terms, any group that calls itself "Taliban" is identifying itself as against the government in Kabul, the U.S., and U.S. allies. Our job is to understand which groups are truly dangerous, which are irreconcilable with our goals for Afghanistan--and which can be fractured or persuaded to rejoin the Afghan polity. We can't fight them all, and we can't negotiate with them all. Dropping the term "Taliban" and referring to specific groups instead would be a good way to start understanding who is really causing problems.
So while pieces such as the 'Field Guide to Moderate Taliban' are entertaining, they are hardly instructive. Unless one subscribes to the notion that we can either win militarily in Afghanistan, or that we must withdraw posthaste, negotiating with amenable elements of what we refer to as the 'Taliban' is a necessity. This will, of course, not bear any fruit unless accompanied by a regional strategy that includes Iran, Pakistan, India and Russia.....and an answer to the poppy production. But it can be the first step.