This is the airline industry we are talking about. These are the people that don't hesitate to kick your teeth down your throat every chance they get. Change fees, redeposit fees, expedite fees, etc.
If they feel the need to revise a policy that benefits the customer, and you can maximize its benefit to you, do so. They consider you, the paying customer, a nuisance most of the time. There is no need for you to "play nice" or try and understand the "spirit" of the policy.
On the morning of March 18th, I was supposed to begin a trip, but had to completely cancel the trip at the last-minute for personal reasons. Because I didn't reschedule and pay $100, the entire ticket was lost. However, that afternoon troops moved into Iraq, and at about 10PM I read on FT that the airlines kicked in their wartime travel policies allowing 1 free change. Just before midnight, I called the airline, made some date changes, and used the ticket in April.
I have also paid a redeposit fee this year on a ticket that was canceled because of my wife's pregnancy. (No waivers for that: I got a hateful lecture from an airline employee about how I'm trying to cheat the system with the medical excuse.) Therefore, I don't feel guilty about "working the system". We, the paying customers, are the Enemy.