If you don't need the bank it is the "smart" way to do it as you will be eligible for more pay if something happens to the scheduled flight. Some will argue that it screws the airline you have a ticket on; fedex's fault. If I don't have another flight scheduled I always forget to back end deviate as that protects all the guys in the crew for extra pay. Domestically NW refunds the Cat Y fare if the ticket is not used.