Well, of course people don't surrender when they think they're winning. There haven't been a lot of outstanding successes recently. There are some high-profile individuals who were formerly in the Taliban who are now more or less with the government, or at least are in Afghanistan and not with the Taliban.
Certainly the communist regime of Najibullah, or I should say the post-communist regime of Najibullah, had some success, actually, in stabilizing parts of the country through agreements such as you spoke about, agreements with elders that allowed fighters to keep their weapons as long as they didn't attack the government, things like that, at least as a temporary measure. But it was never possible for him to stabilize the country, because the mujahedeen continued to receive support through Pakistan.
As long as there is, from their point of view, a part of Afghanistan that is not under the control of the Government of Afghanistan because it's in the tribal agencies and in Pakistan, and as long as that area is also not really controlled by Pakistan and Pakistan does not do more to effectively shut down that recruitment centre, then there is a vast reserve that they have that makes it very difficult to create conditions for that kind of political discussion, although it can be done on a local basis within Afghanistan.