This is the part where I see if I can figure out what exactly Uncle Brynden is trying to accomplish this season.
From what we saw in “The Broken Man,” Uncle Brynden appears to be taking the position of: fuck the Freys.
He’s telling the Freys they can go ahead and hang his nephew, but then again he’s also doing that with the understanding that they have no intention of hanging his nephew.
The question, then, is: what is Uncle Brynden’s plan if the Freys DO hang Edmure Tully?
If Edmure dies, but Brynden keeps the castle, then Brynden becomes Lord of Riverrun, but does he actually want to be Lord of Riverrun? If he keeps Riverrun, and also gets Edmure back in one piece, then Edmure is Lord of Riverrun and Brynden is one of his household knights. Is that his goal?
If I’m really honest, though, I want to figure out what the Brotherhood’s angle is. I want to know whether the Brotherhood is allied with the Blackfish, and if so, what they’re trying to accomplish.
Let’s face it: I am already working from the assumption that the Blackfish is in cahoots with the Brotherhood Without Banners. My brain is too scrambled to add up the evidence from the ground up, so I’m going to play with this idea of Blackfish in the Lady Stoneheart role. It’s probably bullshit. But it’s something I can throw against a wall for the time being.
Assuming we’re not getting Undead Catelyn Stark on the show—and at this point it would take a miracle to make Undead Catelyn Stark happen—we should be wondering what the Brotherhood are trying to accomplish, and what has moved them to start massacring Riverlands Hippies to meet their goals. The Riverlands Hippies are not the enemy, they’re just in the way of food and steel and other cool stuff the Brotherhood need to do whatever they’re doing, but they’re not above killing large numbers of nice people just because they’re in the way.
Meanwhile, Blackfish makes sure to tell Jaime they have enough food in the castle to keep them inside for two years. Perhaps Uncle Brynden took over the Brotherhood and they’re the ones who got all that food together.
We also hear from Walder Frey that the Brotherhood is giving the Freys a hard time. Blackfish is fighting over his castle with the Freys and so far he’s on the winning side. This doesn’t necessarily mean the Blackfish and Brotherhood are working together, but their interests certainly seem to be well-aligned.
At the parley with Jaime on the drawbridge, Blackfish asked after Sansa and Arya, basically word-for-word from the book.
Then next week, it looks very much like Brynden is going to refuse a deal with Brienne to give up Riverrun and fight for the Starks. Which suggests that he doesn’t really care about his Stark relations nearly as much as he cares about antagonizing the Kingslayer and obstructing the Freys.
If the show is putting Blackfish in the Lady Stoneheart role, then his motive is simply revenge, and he’s telling the Brotherhood to fuck up as many Freys as possible as punishment for the Red Wedding, and if they happen to massacre some peasants while they do it, Blackfish won’t let that bother him. If his motive is revenge, then he honestly doesn’t care whether Edmure lives or dies, doesn’t care about the remaining Starks, doesn’t care that he’s hearing terms from his grand-niece Sansa’s new sworn sword. He cares about wiping out the Freys, and he’s letting the Brotherhood do his dirty work for him.
However. Next week, Sandor Clegane is going after the Brotherhood, while Blackfish has to deal with the Lannisters and Freys besieging his castle. I think Blackfish is prepared to go down with his castle rather than surrender to anyone, but the question is how many more people he’s prepared to take with him.
Of course I could be totally wrong about all this and nothing I said above is applicable, but for the moment, it answers a lot of questions.