The CS Monitor has a good article on the changes to our counter insurgency effort. The article describes what the troop surge was intended to do. It was not designed to escalate the conflict but to put a counterinsurgency plan in place to try and stabilize Baghdad. Since the troop surge has pretty much been scuttled, the new commander will have to try and change policies without having the personnel in place. The article says that the new commander General Petraeus will have to try his counter insurgency with only about 3/4s of the manpower he thinks the task will require. The general will try to make up the gaps with a contract work force made up from the militias.
It is human nature that you have to invest a great deal of manpower to affect a successful policy change.
Now, the one real big problem I have with Bush's troop surge is that request did not include an indication of how long the troops need to be surged. The term surge implies a short duration, I wish reports on this issue included the duration.