So I'm not too good at journaling, I saw this topic more as a place to share questions and find answers. I'm hoping someone would be willing to share their opinion with me.

"How would you place a line of action on a figure with a twist in the trunk?"

I've been following along with Marc Brunet's Term 1 content but I can't find a good way to do this.

It feels like the line of action is a good way to hang the three boxes off of when the figure is either front or back, but when they're twisting, I'm torn between running it down the center of the form or trying to map the spine and where it'd be even if it was hidden.

I'm not really satisfied with either of the solutions I've come up with so far. Does anyone have any suggestions, or know a better way?

I think this looks good, I do it similarly to number 2. Dont sweat the boxes to much until you have had some perspective practice in my opinion. Focus on identifying the direction of the main plane is what I would do, then once you get perspective you can add the boxes. This is a particuarly difficulyt pose to box because many of the edges basically overlap each other. Here is how I tackled it. Dont mind its kind of messy but if it doesnt make sense let me know. For the LOA dont sweat being perfectly accurate you are looking to capture the motion or flow of the pose.

Thanks for the feedback! Using it to identify the direction of the main plane sounds like a great solution. I'm going to try it that way during my next practice session.

I noticed the rib box in your example cuts off a little past the breasts. Is that because the model is so twisted, or do you think I'm trying to make the rib box too long? I'm asking because I noticed that while I can do proportional rectangles when the model's neutral, as soon as they're twisting, I start tapering the rectangle like crazy to make it fit within the model like in my first example.

No problem, I cut the green line of the box there to indicate the lateral side of the chest. I do I think the plane on yours is a little small. Think about it like the area of her chest above her right breast should also be in the chest plane. One thing you might try doing if it is hard to visualize this way is to make a shield shape for the chest. This is how I think about poses when doing gesture drawing. Like this

Hopefully that is helpful. If it doesn't make sense please let me know.