The Giants barely won the first Dallas game and the defense benefited from some timely interceptions to squeak out a 2 point win. Defense still gave up over 30 points and that was with Romo throwing passes directly to our secondary. In addition to Romo's charitable contributions, Jason Garrett pulls a gilbride by going away from their completely dominating run attack. If that doesn't happen, perhaps the warning signs are a little more evident earlier in the season.
That win and the beating up of the NFL basement teams gave this defense a false sense of self.