Until the day the Bengals win the Super Bowl (IF that ever happens), the 2005 Bengals will always be my favorite squad of all time. That was such a fun team to watch. However, if I'm not mistaken, their final 2 losses of that year is what cost them a first round bye. KC was the final loss, who finished 10-6 that year, so losing that seems somewhat understandable, but losing the prior game to lowly Buffalo is a horrible memory that sticks out.
I look at that 2005 playoff game as one of the most pivotal games in the history of the NFL. One team's fortunes skyrocketed afterwards, to the tune of 2 super bowls and the other's plummeted, as we are still in search of a playoff win. Up until that point, the post 1970s Steelers were known as the team that always choked on the big stage, and the Bengals looked like they had a dynasty in the making. However, even if they win that game, they didn't have the D to shut down Peyton Manning and co. the following week.
As for Palmer, in addition to the knee injury, I think an equally crucial break in his career was him choosing not to have the Tommy John surgery in 2008. Arm strength never recovered.
Despite all this, I still wear his gameday jersey on Sundays sometimes bc I'm too cheap to buy a new one