Yeah, those two games really left a bad impression
But a quick look at the entire season shows this defense has not fared well against decent offenses, let alone the elite ones.
The defense was adequate against Buffalo twice and the Jets twice, helped by Sanchez's gifts in the second game. They did a nice job against a Falcons team that won't make the playoffs, and they hammered two of the worst teams at the time in Tennessee and Tampa Bay. They also performed well against Carolina with Matt Moore (who?), and Chad Henne in one of his first starts for Miami.
Of course Henne would come back to torch us in the second match-up. And they were destroyed by the Saints, and collapsed against the Colts. The secondary was dissected by Kyle Orton (yes, THE Kyle Orton). Perhaps the best performance all year for the D was against Baltimore, a team that might make the playoffs, but we were really holding on at the end.
There's no shame in giving up 35 to Indy or 38 to New Orleans, though the way they gave it up was a bit sickening. But all of the great performances were against awful competition. Even against even a decent offense (like Miami or Denver), the defense has been quite vulnerable.