The methods include wrapping explosives into the gears and slats of vehicle chassis or into carefully concealed chambers, he said.
He said Iraqi authorities have requested scanners capable of looking inside sealed portions of vehicles.
It seems that this isn't so much the Iraqis suddenly losing as it is a case of the enemy adapting. That happens in war. The enemy adaptation itself came from the success of Iraqi security forces in finding and stopping the older method of building car bombs.
Wars are not waged by two static entities. The Iraqis will adapt to the new enemey tactics and defeat them. And then the enemy will try to adapt to that. It will continue until one side finally defeats the other for good.