How interesting! Animators have long used mirrors to model and capture facial expressions. I'd never thought of using that technique for writing, but I can see how it would be beneficial.

Will, file this under Whatever It Takes. As John says, "Anything’s fair game as long as it works." This type of thing is a big reason why I burrow into books, magazines and online resources to surface interviews with writers. Their processes are both fascinating and instructive. Also it's why with every interview I conduct, I ask the same set of craft questions. You never know when something you read about a writer's process may resonate with you and inform your OWN process.

This is why I don't write stoner comedies.