They might have actually altered that stuff in service to the character arcs. It's a bit much to expect a TV audience to wonder for the next 40 weeks if Arya is getting knifed or raped or something by Yorren, so they used the CoK scene to show off where she was going next. Even if Yorren's identity and good intentions are not questioned, by showing Arya with her new road companions establishes that she has not been "rescued" or in any way removed from danger. While she might be in the care of an ally, she is also now in greater physical danger than she might have been had the Lannisters caught her. She has value to them as a hostage, and the rules protecting noble girls apply to her. On the road with Yorren and his criminals, she faces entirely different dangers. Beating up Hot Pie as the final scene of the season would only serve to establish her as a badass (for a kid) and leave viewers confident that she can handle her shit. It would be better to move the fight to the beginning of next season, to establish her violent characteristics and budding sociopathic tendencies as a counterpoint to her fighting ability. Beating a guy up seconds after your dad's
beheading gives you credit with the audience, and they're less likely to note her nasty traits.


They did have the army fight Tywin, so they can still bring it up. I believe you are also exaggerating the strategic difficulty Robb faces. Robb's forces were not set up for defeat in detail as you suggest, but rather they had Tywin trapped. That's why he fled to Harrenhal. Once there, the problem was that Robb and Roose could not converge on him to take such a secure fortress against an army the size of Tywin's host. They didn't have the siege train and Gregor & Lorch & Hoat had orders to lay waste to all the lands in between their position and Harrenhal, which would have made it very difficult for the northerners to supply their forces if they tried to besiege the Lannisters in Harrenhal. Once Tywin fled to Harrenhal, he was no longer in between Stark & Bolton, but he WAS in position to attack them if they joined up or to move to the defense of King's Landing. Tywin's problem was the number of separate enemies he now faced, which limited his options, because if he moved against one, the others might pull tricks to his detriment. He had the numbers and power to be fairly confident of a tactical victory no matter what he did, but any such fight might have strategic costs. He defeated Roose Bolton's reduced force on the Green Fork, but had he known Robb was moving on Riverrun, in other words, that he faced two different armies, he would never have advanced to fight Bolton's force. Tywin was not afraid of the OUTCOME of any battle, he feared the political or strategic problems he fight get by getting stuck in a fight. That was why Robb raided into the West, to lure Tywin out of position just as he had with Bolton's army in GoT. Robb COULD have fought Tywin with a united Northern army without even crossing the river or paying Frey's price, but he did not want that, which was why he came up with the idea of splitting his force to go after Riverrun. After the battles of the Green Fork, Whispering Wood and Riverrun, he had even fewer men and less desire to fight Tywin head on and the Lannisters knew it and Tyrion points out as much to Cersei. That was Edmure's problem - he was thinking with his ego, and thinking of the immediate threat and ignoring the strategic concepts involved. Even not knowing Robb's strategy, he should have been thinking like the Lord of Riverrun and protector of its lands, and WANTED Tywin to pass Riverrun unmolested and out of his lands back into the West. By bloodying his nose, Edmure forced Tywin to remain in the Riverlands, raping and plundering Edmure's own vassals and his king's subjects. That's why even his own uncle was ready to rip him a new one.

Regarding the TV show, all they have to do at some point is mention the remnants of the northern army that fought Lord Tywin while Robb was lifting the siege of Riverrun. They really have not given themselves any troubles here, or irreparably altered the story. I think subsequent seasons are going to be greater departures from the books, because GoT was the most self-contained and straightforward book, and the least dependent on old history and pre-continuity to explain the events and actions. Much of the history of the old rebellion and the various houses' interactions with the Targaryens are still a mystery at this point and contribute nothing to the story. If the rest of the show is not going to devolve into endless lectures and stories, they are going to have to get a little creative at providing context for the relationships between power blocs and so forth.