Andy Reid fired his DC Juan Castillo in what has to be considered a panic move by him. Reid has pressure to win this year and he is apparently willing to sacrifice loyalty of a long time, well regarded (OL) coach now coaching the defense, rather than going down with the ship. It's a little curious that he did this. It is definitely questionable that Castillo deserved to be fired and that he is the cause for the Eagles mediocre 3-3 record. Consider: Eagles defense is in the top half of the league (nearly in the top third actually) in both key team defensive statistics. They are 12th in the league in yards allowed per game and are 13th in the league in points allowed per game. That's not bad statistically and if you throw in the fact that the Eagles are second worst in the league in turnover differential, meaning that the defense has had many more possessions to defend than the average team, you could argue that the defense has actually been much better than their statistics indicate. Furthermore, I could argue that if there is a disparity between yardage and points, that goes to the coaching staff. What I mean is - if the team is only average in yardage statistics (on offense or defense) but their points allowed rank is much better than the yardage, it might indicate that the coaches know how to squeeze every ounce out of the native ability that his unit has. Conversely, if points are a much lower rank than yards it might indicated that the players have the ability to make plays and get yards, but the coach can't push the right buttons to convert it into points. That might indicate that Castillo is doing a reasonable job - because the defensive rank in yards and points is roughly the same.
Now consider Reid's offense. They are ranked 11th in the league in yardage gained per game, but are ranked 31st in the league in points per game. You could certainly infer that because of all the turnovers, penalties, questionable play calling in the red zone and strategic flaws in the offensive plan that it is the offensive coaches that show an inability to convert yardage into points. It sure looks like it is the offense that needs to be tweaked, not the defense. But that is Reid's offense and he can't fire himself. I wonder if the next shoe to drop is change at the QB position. It would be a huge gamble by Reid to replace Vick, it will probably splinter the locker room and I doubt he will do it. But when teams and coaches are panicking - who knows?