Weeks 3 & 4 in the Rodney Yee book focus on Opening into Vulnerability and Allowing Receptivity, which really go hand in hand as far as I'm concerned.
Chapter 3, the Opening into Vulnerability chapter, is about doing backbends, which I have a love/hate relationship with. I'm pretty flexible, especially in my front body and back, but what I'm working on now is having the strength to back it up. My legs have gotten stronger to protect my knees and hips, but if my front body and back don't get stronger I'm afraid of hurting myself when I go too deep into a backbend, or get a little too overzealous trying a backbend or other pose that I can't safely bring myself back out of. Also, the more I think about and read over what I've just read, the more I notice how it closely it echoes the personal struggles I face, and once again finding myself amazed by how every facet of yoga has intertwined itself into my life.
In Chapter 4, Rodney Yee opens with a nice bit about how when we come up against a barrier, it is important to back up enough to observe, breathe and assess (rather than try to confront an obstacle head-on like a battering ram and create a struggle). This is a constant battle for me both in my life and my yoga practice because there is such a fine line between trying too hard and not trying hard enough, between hanging on and letting go, and I feel myself stumbling this line every day of my life, with every decision, big or small, that I am faced with. At least with my twists, I know my limits!