Here are five thoughts on the Eagles' announcement Wednesday that Juan Castillo will be their next defensive coordinator:

1. If you missed the press conference, here's the Cliff Notes version of how the Birds arrived at this decision, which no one saw coming: Castillo has been in Reid's ear for years, telling him that he's a defensive coach and would like to coach that side of the ball. Reid always listened, but wasn't willing to move Castillo unless he found a replacement that was just as good to coach the offensive line. After Reid fired Sean McDermott, he thought about promoting Castillo to defensive coordinator, but only if he could lure legendary offensive line coach, Howard Mudd, out of retirement. Once Reid was able to do that, he decided to make the move.

So, are we buying this version of the story? Given the way things played out, it seems like a reasonable explanation. Big key here: Don't underestimate the role Jim Washburn had in those whole thing. An NFL Films piece called Washburn and Mudd "best friends" and showed them spending part of their offseason together motorcycling across South Africa. Why would a coach who turns 69 years old later this month (Mudd) want to return to the league? My guess is it was two-fold: a.) To coach with pal Washburn and b.) A financial offer from the Eagles that was too enticing to pass up.

2. As for Castillo's hiring, let's start with what we know. He's known for his work ethic, and I've heard players say nothing but great things about him in the past few years since I started writing about the team.

At training camp, it was common to see Castillo on the field with several offensive linemen in the afternoons when there was technically only a special-teams practice being held. What was perhaps more impressive was that Castillo was often working with backups and guys who wouldn't even end up making the roster.

I have no idea if this move is going to work out, but what's clear is that Reid was going to go with his guy. It's been written several times, and it's true. Reid is in a critical phase of his career. If he doesn't get this team over the hump in the next two to three years (his contract runs through 2013), both Reid and the organization could very well choose to part ways. There's a chance this was the last defensive coordinator Reid will ever hire in Philadelphia. And so he went with a guy he's familiar with, a guy he can trust.

The other part of Reid's comments that stood out was when he was explaining his own rise to becoming a head coach. Jeffrey Lurie and Joe Banner took a chance on him even though he hadn't been an offensive coordinator. You get the sense that Reid really appreciated that and was proud of that. I think it had something to do with his decision to go with Castillo.

3. Don't forget that the Eagles still have to find a linebackers coach and a defensive backs coach. Those hires could come from within, but make no mistake: they are of huge importance. In Washburn, the Eagles got what most consider the top defensive line coach in the NFL. Castillo brought Washburn's name up several time during his press conference. It's clear that he is a huge asset and someone Castillo is going to lean on. That's smart because Castillo is going to have his hands full. He's never called a game before in his life. And he needs capable assistants to coach the linebackers and secondary.

4. At some point in the last 12 years, the Eagles became one of the most unpredictable franchises in the NFL. I'm not quite sure when it started. There was the addition of Terrell Owens back in 2004. There was the signing of Michael Vick in 2009. The decision to trade Donovan McNabb within the division last year. Starting Vick ahead of Kevin Kolb during the season. Firing McDermott after two seasons. And now this.

If Reid is feeling pressure to do things a certain way from upper management, it did not show here. While it's fair to question whether the McNabb and McDermott moves were his alone, the unconventional decision to go with Castillo would appear to be Reid's and Reid's alone.

5. The biggest question that remains unanswered (from a football standpoint) is how the defensive scheme will change. Reid said terminology will not change. And the impression I got from the press conference was that the defense is not going to deviate greatly from its approach of getting after the quarterback.

Say what you want about McDermott, but he was an idea guy. He had a vision of how he thought the Eagles should play defense, and he wasn't afraid to try new things or come up with out-of-the-box ideas. Castillo has been so focused for years on coaching the offensive line that you wonder if he has those same ideas running through his head. Will the Eagles rely on the blitz? Will they rotate players in and out of the game? Will they drop linemen into coverage? Those are the questions we won't have answers to until the team is allowed to practice again, which might not be for six or seven months, depending on what happens with the CBA.

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