I believe any sane ISI or Army would play double game, we already have India on our eastern border and it would be quite fatal to have another Enemy (or at least not friendly) state sitting on our western border. What Pakistan Army or ISI is doing is right though not very eqasy to handle.
I disagree, trying to appease Taliban/Alqaida (in one side of the game) is actually countering the alliance of US+Afghanistan govt, that way we are converting bigger friend into an enemy(like).