What you describe sounds very similar to my take on the Rubber Ducky method, except with writing things down instead of talking out loud. I think what works is the act of putting your thoughts out into a form you can then turn out and think of as external, then respond to. This enables you to look at it from an "outside perspective" even if it's literally your own perspective. It's hard to challenge your own ideas if you don't put yourself into that seat.