Grey's Anatomy writers Tony Phelan and Joan Rater, who penned last night's episode, have posted some thoughts on "Before and After" on the show's official writers' blog.

Here are some excerpts, with a link to the full column below ...

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I thought that the thing we really can do with this crossover is show another side of Derek, I just wasn’t sure what that side was. So we started to talk about it.

We always imagined that Derek and Addison met in med school in gross anatomy class and basically fell in love over a cadaver. I know, romantic, right?

But for them I’m sure it was.

We decided Derek and Addison were probably the first of any of their friends to get married and it was probably an amazing wedding and then someone in the room told a story about this wedding they went to once where the guy sang a song he had written for his wife about how they met and fell in love.

Ten years later, whenever anyone who was at that wedding sees this couple, they demand that the song be sung. Hearing this story I suddenly knew that Derek had to be that guy. Because I love that guy. And because it tells you about the group of friends, who all remember the song.  

Addison and Derek: The Seattle Grace days.

They all thought Derek and Addison would be together forever and now here they are, ten years later, divorced. And Naomi is divorced. And Archer is maybe going to die. And so they need the song, they want the song, they want to go back 10 years, when it was all so hopeful and happy and no one was dying.

Now here’s the thing – they don’t really want to go back. Derek and Addison don’t want to go back to being together, that’s not the point. The point is ... It’s like when you look at a picture of yourself from ten years ago and you can’t believe how much you’ve changed.

And you don’t really want to go back there, because you like your life and everything and you certainly don’t want the bad haircut back or the ugly bridesmaid’s dress, but you look at yourself and your old friends in the picture and you realize you haven’t spoken to that friend in years, that person you used to speak to every day, EVERY DAY, and you suddenly, desperately miss that person and have no idea how you got to the point where you don’t even know where they live.

THAT is the feeling we wanted this episode to have.

Follow the link to continue reading the writers' blog.

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