We're in an orientation class at our new home, and one of the other couples in the class is dual military. They have a lot of questions about their situation, and sometimes the people who are presenting the class seem confused by our dual military friends.
One interesting issue that has come up is the payment of Dislocation Allowances (DLA).
It seems that the regulations say that a dual military couple is only authorized one DLA (the higher) unless there is a substantial reason that the PCS move requires them to established two new households. Whether or not each individual member does or does not have dependents also impacts the availability of multiple DLAs.
If a dual military couple PCSes from one location to another together, there are never two DLA payments because they are not setting up two new households.
If a dual military couple PCSes from the same location to the same location, but at separate times, they are still not necessarily authorized two DLA payments. The Joint Federal Travel Regulations (JFTR) has a rather complicated table called Table U5G-3, and it can be found on page 405 of the current edition, after Chapter 5 Section G.
If a dual military couple PCSes from two locations to one location, only one DLA is authorized.
If a dual military couple PCSes from one location to two different locations, far enough apart that they are establishing two new homes, two DLAs are authorized.
Some people feel that this rule is not fair, and that each service member should receive their full DLA as part of a dual PCS move. Regardless of your opinion on that, it is a generous improvement over the previous law. Prior to 2001, if a dual military couple did not have any other dependents and moved into government housing, neither member was authorized DLA.
For more information, you can look in the Joint Federal Travel Regulations, Chapter 5, Part G. The language about dual military couples begins on page 402 and continues through page 406.