The General meant a shifted Durand Line **westward**. I imagined he meant the Pashtun areas of Afghanistan included in the new Durand Line. The General also said that there are refugees inside Pakistan who don't want to go back to Afghanistan--and so logically the Pashtuns inside Afghanistan wouldn't mind being part of a much more prosperous Pakistan in one form or another.
Guys: The Durand Line is a NON ISSUE! Per my understanding it arose to prominence when it suited Dawood Shah after he overthrew Zahir Shah (in 1974?) for domestic political reasons. After that , Zulfiqar Bhutto decided to put them into their place by getting involved in the Afghan affairs. Speaking of these things, Afghanistan has been in a mess since the removal of Zahir Shah and they have ONLY themselves to blame for that.
Practically speaking, Taliban should take over all the Pashtun areas on the western side of the Durand Line and provide Pakistan a buffer. That kind of state could be part of some Confederate of Afghanistan with great autonomy. I don't think Talibans have the right to take over areas in the north or anywhere else where they are despised.