Isn't that the worry. The issue with reduction in aid is still the underlying fact that some form of aid will continue. If the only purpose served by aid is to prop up an unjust system, then Pakistan can make do with far less aid.
The Pakistani political parties and military leaderships will pass over any reduction in aid straight to the people. Anyhow, how many billions are required to keep a generic Zardari type figure happy. Less aid may cripple the economy, but would only do so a few years before the pace of population growth does so itself. On the other, those in charge will still be able to buy European mansions, cars, and education.
Africa and its many failed nations are great case studies to look into; for the nation may have failed, those who run it continue to prosper. And until those who run it, see no reason to change it, why would Pakistan change at all.