Revealing mistake: At the end of the first fighting session, after Tris' opponent has Tris on the ground, Eric gives Tris the signal to get up and the opponent punches her one last time. It is noticeable that the final punch does not hit Tris, but she still reacts anyway. (00:36:15)
Continuity mistake: When Beatrice meets up with her brother Caleb helping out the older lady, Caleb asks Beatrice if she wants to get the other bags. Caleb is first shown to be directly facing Beatrice. Next shot, he's suddenly turned almost 90° to the right with his head now turned in order to face Beatrice. (00:05:30)
Continuity mistake: When Al and the two masked people are attacking Tris, Four appears, throws Al off Tris and he hits the wall. As Al hits the wall, it appears to have nothing lit on it, then from a side angle, green lighting has suddenly appeared. This has nothing to do with the camera angle. (01:19:40)
Continuity mistake: When Beatrice and Caleb are walking through the streets and Caleb talks to Beatrice about the older woman, Beatrice turns her head to Caleb as she says she was thinking about helping her. In the next shot, she's suddenly looking directly forward. (00:05:35)
Continuity mistake: As Tris is doing her first fight session, she dodges her opponent's hit and the majority of her hair is shown going over her shoulders. In the next shot, it's now only a few hair strands over her shoulder whilst the rest of her hair is resting along her back. (00:36:00)
Continuity mistake: When Tris is on the zip line, after she does her flying impression and passes by a building, the shot returns a close-up of Tris where there are strands of hair being blown across her face. Next shot, her face is free of any hair strands. (01:01:30)
Answer: There aren't really obstacles. On a zip wire, there isn't really much scope for manoeuvrability. You follow the wire.