Dalton imploded in all three playoff games. As was stated, it's not that he played badly, it's that he was downright horrible all three games.
But, most importantly, where do you get small sample size from? Dalton has failed for three full seasons,....that's 51 games out of 51 games to deliver under pressure. Whenever there's pressure, he folds like a pup tent in a 30 MPH wind. Don't make me pull out the stats. I shouldn't have to. We've all seen it.
Mike Brown has a definitive problem. There's really only one solution, though. Draft a QB in the 2nd Round and wait out the 2014 season without an extension. If Dalton proves himself by showing he can perform under pressure for the first time in his life, then there's a little leverage to work with now that there's a decent QB with a year of watching and learning on the team ready to be given a chance should the price on Dalton be too much. If Dalton shows that his ceiling is likely to be a QB who can win some regular season games if everything around him is just right, similar to Matt Schaub's situation in Houston, but that Dalton can't throw a pass under pressure, then this isn't the guy you want to give $10M/yr to, yet alone the $20M that Dalton's agent will command and the franchise-tag will be for Dalton in 2015. You let him go and get 3rd Round compensation for him in 2016, or tag him once if you feel the 2nd Round QB isn't ready to be handed the reigns.