The other services have not had this sort of option. In fact the navy seems to have the opposite philosophy.

I know a navy reserve O-5 who who was already IRR who put in for retirement (22+ years). Within a week he had orders to Iraq.

AD Navy tends to do the same thing with JO's who drop their letter. They spend their last 10 months of "shore duty" in the sand box.

Maybe this encourages retention