I'm not sure what the problem is- AA is not charging military on orders for extra weight. I flew back from Narita to DFW on AA three days ago. I was on military orders, and had a ton of gear from my deployment in the Tokyo area. I was ready for a fight on this issue, but when the weight of the suitcases came up, the agent at the AA counter told me as long as I had my orders, there would be no charge for extra weight.
for what it is worth,
-Aloha