Anchor: As a technical matter, it should be noted up front that there is no requirement that the mailer or the competitor really perform any particular piece of work, only that the mail be presented so that the postal service2 does not have to do that piece of work.
Entailed: The requirement is only that mail is presentable so that the postal service doesn't have to do that piece of work.
Contradiction: Mailer or competitors are required to perform all particular pieces of work.
Contradiction: It's been a colossal failure.
Contradiction:  After the ships took their stuff back the visitors headed out on the empty boat and stayed in the area.
Contradiction: I love being out in the woods with just a bedroll and the stars. 
Contradiction: The longest suspension bridge in Europe is across Rio Tejo.