I agree that the tags won't help much, however I must say that their baggage tranfer at PHX is pretty good.

Last year we were on a flight that arrived at PHX an hour late due to a mechanical problem, our flight to TUS was leaving from a nearby gate, they had just closed the door to the plane when we arrived, they re-opened the door to let us on, and then quickly departed. I was amazed to find that our bags had made it on the flight too!

If they could just get their planes going.