One of the things that bothered me about "The Dragon and the Wolf" is how the Sansa/Arya storyline clearly omitted information when going from Arya and Sansa fighting each other to them both turning on Littlefinger. While it's obvious the show was holding things back as an absurd means to surprise the audience about who was really the focus of the inquest, it turns out that there was a scene between Sansa and Bran that was cut out. From a
Variety interview with Isaac Hempstead Wright:
It’s clear after Sansa turns the tables on Littlefinger that she has had some sort of conversation with Bran, but we don’t get to see it. When did it take place?
We actually did a scene that clearly got cut, a short scene with Sansa where she knocks on Bran’s door and says, “I need your help,” or something along those lines. So basically, as far as I know, the story was that it suddenly occurred to Sansa that she had a huge CCTV department at her discretion and it might be a good idea to check with him first before she guts her own sister. So she goes to Bran, and Bran tells her everything she needs to know, and she’s like, “Oh, s—.”
While the inclusion of this scene wouldn't have fixed the overall problems, it certainly would've smoothed out some of the wrinkles. I guess this means Arya really intended to scare the shit out of Sansa.