If Raven were a dog I would say that she suffers from barrier frustration. She does not like to be contained, and she does not like being stuck in place A when she wants to be in place B. At her worst she will run fence lines with her head over the top and her chest brushing against the posts, and even at her best she is prone to bolting through gates.
When Raven first arrived I had a stick (or broom or whatever) in-hand whenever I let her through a gate. She soon learned that calm and collected behavior earned her the right pass through while drama queen antics earned her a lot of hard work on the wrong side of the fence (so to speak). But sometime over the course of the summer she perfected the art of bolting from a seemingly-calm-and-collected standstill and gate passages became uncomfortably unpredictable. Over the past week I have been (1) haltering her, (2) doing some ground work, (3) passing respectfully through the gate, (4) doing some more ground work, and (5) unhaltering her. It seems like a ridiculous step backwards, but it also seems to be working -- she is more relaxed each day. Next week I will start surprising her with unassisted passages and, hopefully, we'll get back to where we started.