The air dam must not be all that important (contrary to earlier training) because Ford decontented it. The 2000's didn't come with it, and I think that it was dropped sometime in the 1999 model year.
There seems to be more horns replaced under warranty on the ones without. I suspect that the horns are subject to much more rain intrusion since they are mounted so low and without any remaining shielding.
It is also a lot easier to change the oil filter when the air dam is not in the way.
