A Najaf-style fight in Sadr City I think is going to happen regardless. We just have to do it right and we HAVE to get the ISF involved, if not take the lead.
I think that will be a watershed moment, when we take an Iraqi brigade (with aperhaps 50% Shi'a manning level), stand them up nice and neatly in formation, and tell them they are the main effort in an attack to seize mission in Sadr City. I'd like to see the look on their faces.