If I'd done that I couldn't have context-switched back to the documentation so easily!
Nah. I get what you're saying, and it's a great idea. Sometimes I do go for a walk. More often I do dishes. Those are both, however, higher-commitment, more time-consuming activities than flipping to a different window. If I remember correctly, my sticking point that day felt like a small one, and so the distraction / break I felt like I needed was correspondingly small.