I suspect that the training period of an Iraqi cannot be predicted with the same accuracy as an American because the infrastructure isn't there. American boot camps have been around for decades. They have all the facilities and supplies they need, with domestic suppliers. They exist within friendly surroundings: No one in the US is trying to kill recruits simply because they joined up, nor their trainers just for being there.

And if there are any American "insurgents" signing up just to gain access to bases in order to wreak havoc, I haven't heard about it.

Maybe it would be more effective, long-term, to bring Iraqi units to the States for training... but we still have to supply them once they've returned home.