Maybe it's just me, but when I was reading the glare-filled, courier-fonted original pitch, I spent more time concentrating on how things hadn't changed. While it diverges in a lot of places, there were a lot of things that remained ultimately, in terms of what a writer needs to push a plot in a certain direction, more or less serving the same purpose.
I'm going to try to approach this as a writer, and someone who's watched closing in on hundreds of hours of GRRM's interviews, in hopes to break down what has and hasn't happened and the potential logic behind those changes.
What's the same:
- The same characters who are died, are still dead (less Tommen and Myrcella, who aren't mentioned by name in the pitch so it's hard to tell whether they were even in the original version, and the wee Stark-Lannister babe, who doesn't exist in the books at all and therefore doesn't count).
- The same characters who are alive, are still alive, most notably the principal five characters that GRRM intends to survive to the end - Tyrion, Daenerys, Jon, Bran, and Arya.
- Sansa still sort of betrayed her family to the Lannisters, by telling Cersei of her father's plan to leave the city.
- Tyrion's "disenchantment" with his family.
- Tyrion being framed for the murder of his family members is still his ultimate turning point.
- Winterfell still burns.
- Drogo still kills Viserys.
- Daenerys still kills Drogo (though indirectly).
- Where we're at now, Dany has escaped into the Dothraki sea with a "trusted friend" of sorts, and if the allusion in her final chapter isn't just a red herring, she will find herself facing a Dothraki horde, with the ability to turn them back to her favor (namely, dragons) soon.
What has changed:
- Sansa marries Joffrey.
- Catelyn stays in King's Landing long enough to get her children out.
- Catelyn does not accompany Robb in his battles.
- Catelyn and Arya return to Winterfell and take Bran to the wall after the burning.
- No epic Robb vs Joffrey battle. Bummer.
- Benjen doesn't disappear raiding, and is the Lord Commander of the Night's Watch (I assume).
- Bran doesn't seem to have anyone "helping" him discover his magic, including Bloodraven.
- I see no mention of Rickon anywhere.
- Tyrion manages to make it to the Wall (which may still happen, eventually, same with Arya making it to the Wall).
- Jaime doing some hella kinslaying, which makes Jaime much more of a villain in this original version than he is in the published version. I can only assume that his hacking his way to the Iron Throne included eliminating all of Robert's bastards (which occurred, though I can't be entirely sure right now whether it was Joffrey or Cersei who made that call), any children that Cersei might have had either with Robert of with him, and Sansa's son.
- There's also no mention of Sansa further on in the pitch, and she's not one of the ultimate five to survive to the end, which is worrying for Sansa fans (myself included).
- No mention of Arya's Braavos storyline, Faceless Men, Syrio, etc.
- No mention of the "War of the Five Kings"; it seems the conflict is between Stark and Lannister alone.
What is still up for grabs:
- Arya/Jon(/Tyrion) romance. I'm of the opinion that the first half of this, at least, can still happen. My theory is that Jon was killed in his last appearance, and spends some time inside Ghost (semi-confirmed, at least the spending time inside Ghost bit), until Melisandre revives him. Since he's died, and his watch has ended, he's free of his vows. But it also might not be safe for him at the Wall. He may have to leave, whether to go North, or, if I'm right, East. I also have a theory about who Azor Ahai/Lightbringer is, but here's not the time to discuss that.
- Benjen being alive and still a crucial player in the events at the Wall. We know he's not Coldhands, despite fan's eager wishes, because Coldhands is over 200 years old, but there's always a chance he might still be out there, somewhere. Or GRRM could have decided halfway through writing that he just wasn't necessary and offed him, leaving a gaping plot hole that will forever haunt us in our darkest dreams. It could go either way.
- Arya, Tyrion, Bran, etc making their way back to the Wall, or somehow coming together with Jon and joining his side against both the Others and the remaining Lannisters. If Tyrion is joining up with Daenerys, which he might not at the rate things are going, he'll end up there. If Jorah decides to return to Westeros and put his pardon to good use, he might end up there. Bran, after finishing his training with Bloodraven, might venture back south to lend a hand to the Night's Watch in their battle against the Others. Arya, man, I haven't the faintest idea how GRRM is going to pull that off, but I don't doubt she and Jon will be seeing each other again, because I have a feeling GRRM intends Jon/Arya to be endgame.
- Jon killing Tyrion. From the sounds of it, the "deadly rivalry" is going to be, obviously, deadly. But for who? Jon, Tyrion, and Arya are all ones who are meant to survive to the last book. But does GRRM mean to or through? At least one of the five mentioned is not going to make it to the last page, and I'd reckon it's not going to be any of the Starks.
- Jaime killing members of his own family. At last we saw him, he was being approached by Brienne, who had just re-pledged her sword to Lady Stoneheart (confirmed by GRRM himself), and he's either about to die or about to join sides with the Stoneheart and the Brotherhood to get revenge on the Freys and his own family. Can I see him killing Tommen and possibly even Cersei? Yeah, I can. And it'll be pretty shocking if it happens, which sounds right up GRRM's alley. "The things I do for love," indeed. Killing Cersei quickly to prevent a long, brutal torment at the hands of the Brotherhood would be the ultimate moment for Jaime.
Totally unverified opinions on why certain changes were made:
- First, Sansa's marraige to Joffrey. This is a long theory, so buckle up. If GRRM didn't intend to have the War of the Five Kings when he sat down to write, then Renly and Stannis would not have made an appearance. Therefore, Renly's queen would never have become a player in the Game of Thrones, and never would have ended up marrying Joffrey. My theory is that the Tyrells simply didn't exist in the original version. But when GRRM saw that there was a hole in Jaime's motivation, or fleshed out his backstory more thoroughly, he had to have seen that Jaime's actions in the original version simply wouldn't work. Couple this with GRRM's obvious joy at making things overly complicated, and you get a war for succession that spans not only Robert's brothers, but other people who see the opportunity of a war to stake their claim. Robb was then joined by Renly, Stannis, and Balon (Theon isn't mentioned in the original pitch either, so they Greyjoys are probably a later addition as well), in fighting against the crown. In fleshing out and worldbuilding, Loras, and then Margaery, came into being. Now, GRRM could have had Joffrey put Sansa aside in a grand Henry VIII fashion, made conflict with the Faith, and had him marry our Anne Boleyn (Margaery), but the way he did it was much less complicated and totally eliminated a lot of threads that would have had to be tied up in other ways (namely, Sansa's child). He complicated, then he simplified. In my opinion, he made the right choice. Things are much more interesting for all the characters involved this way.
- Another possible explination for this is that he adjusted the ages of the characters. It does seem that Arya, at least, was older in the original pitch than she was in the published version, which would require Sansa to be older as well. I would venture to guess that their original book ages probably more closely resemble their current show ages.
- ms_geekette makes a good point, elsewhere, that a couple of the characters in the original pitch have been split into new characters. For example, Benjen Stark's storyline split with Jeor Mormont (perhaps after GRRM decided Daenerys needed a Westerosi council and fleshed out the backstory for Jorah), and Tyrion's Winterfell involvement split with Theon (I'm not completely sure where Theon came from, except GRRM's Lovecraft fanboying). Additionally, much of Jaime's storyline seems to have been given to the Great Tyrell Conspiracy. So I imagine that, with the addition of new characters, old characters with over-burdened plots were lightened to expand the overall cast.
- With the obvious changes in Joffrey's character to make him a weak, unworthy king (harkening back to several Targaryen kings and perhaps making the stance that children born out of incest are doomed, inevitably, to madness), there couldn't have been a battle between Joffrey and Robb because Joffrey simply wouldn't have been on the battlefield. GRRM went on to hammer this point home during the Battle of Blackwater, when Joffrey's true colors were shown. And while Tyrion could have, and had good reason to, kill Joffrey, GRRM decided to make it a bit of a mystery for the readers while still keeping the storyline of Tyrion being framed for kinslaying.
- Let's not forget, also, that Robb still (indirectly) maimed a Lannister. It was men on the Stark side, at the time, who cut off Jaime's hand. These men later switched sides with Roose, but at the time of Jaime's dismemberment they were Stark men.
- I genuinely have no idea why the changes to Arya's character were made. There was the foundation of the plot to take her to Jon at the wall in Yoren wisking her out of the city, but then we have a huge wrench in the plot - Jaqen. The only logical conclusion that I could make is that there had been the prior mention of purchasing a Faceless Man to kill Daenerys, and while GRRM was fleshing out the guild and their religion, he realized how major a faith they truly are. Each of the other faiths have their representitives in the plot: The Faith of the Seven, the Lord of Light, the Drowned God, and now he needed a representitive for the Many-Faced God. He may have intended Jaqen as nothing more as a plot device but he's said that there were characters who, in writing, made themselves bigger. Jaqen's dialogue with Arya alone is fascinating, but then you have his involvement in the escape from Harrenhal. He's made himself bigger at that point and can't be a one-and-done character. Bringing him into the Oldtown storyline is one way of expanding up him, but we, as readers, still lack a representitive for his god. I feel like GRRM probably saw that in order to be as big of a player as he wanted her to be (Arya is his favorite character, by his own admission, right after Tyrion), she needed training. Syrio was a start, but he wasn't enough. So merging these two storylines and having Jaqen as the plot device leading Arya to her training was a necessary event. He must have seen that she wouldn't get training from Jon or the brothers of the Night's Watch, though he may have intended that to happen in the beginning, so Arya needed a detour.
- The deaths of Robb, Catelyn, and the Red Wedding is arguably the biggest change from the book after Jaime's total character overhaul. Everything connected to Jaime had to be changed when GRRM adjusted his character, but the Red Wedding storyline in particular is a pretty abrubt revision. For one, Robb dying in battle seems unlikely considering Grey Wind. Second, other storylines had already changed and Catelyn wasn't going to make it to the Wall to have her doomed run-in with a white walker. GRRM explains quite simply why he got where he got: some wars are won with swords, others with quill and ink. Their storylines had to be wrapped up and the quickest way for a writer is essentially "rocks fall, everyone dies". GRRM has said many times how much he loves Scottish history, and he took straight from two fateful Scottish encounters to create the Red Wedding, tying up the last of that storyline effectively, with a shock, and most importantly without wasting pages. GRRM knew that the characters needed to die, much as Ned needed to die, and he's said that the Red Wedding was one of the most difficult things for him to write and took the longest, but I think many fans assume this was an emotional strain on him rather than just a logistical one of "How can I kill these characters that need to die without dragging on another plot forever?"
If there's something that I missed and you want me to theorize on, just let me know and I'll shove it on the list.