That's a very good question.
First of all, there is no Taliban as such. This is a very broad spectrum of people. Most Taliban are interested in Islam as it relates to Afghanistan, society in Afghanistan, and defence of traditional Afghan values, whatever we may think of them. I would argue that if they think that some minimal attention is being given to these goals and that western military forces are out of there, we would find large numbers of Taliban who are quite ready to simply operate within their own country rather than join some kind of international jihad.
Yes, it did happen—you're absolutely right—with al-Qaeda before, but I think this is an exception to the rule. Afghans have not been, by and large, joining al-Qaeda around the world or fighting elsewhere. So I think it is not entirely a dream to think that the Taliban can be split, as long as they feel that western armies and occupying forces, in their view, have left the country.