Manning played great? Um if I recall correctly, he played one good half the entire playoffs (againts Pats AFCCG) he was awful against Chiefs, and Ravens 1 TD and 5 INT's.
What helped was that their first 2 opponents saw a weak run d and ran every down. The Herman Edwards Chiefs ran almost every 1st and 2nd down and the Colts knew it was coming. Even they could stop the run if they knew it was every play. I think the other team was the Ravens who couldn't throw it if they tried so they did the same dumb thing.
That was always the thing about the Colt D. If you made them play honest, you would gash them on the ground because they just ignored the run and rushed the passer, but if you announced you were running right at them they could play OK.
I know the defense wasn't very good last year, but they weren't disappointing in the play-offs. They probably played better than or as well as they have all season in the playoffs. The offense laid an egg.