It's not a myth FOR YOU. And that's good. But when I talk with others that want to write a book, but then complain they don't have an idea, well THEY are stuck in the myth. They won't come to the computer UNTIL they have an idea. That's the myth.
Even if you don't have an idea, just start writing.
I'll check out PiBoldMo, I was unaware of that. Thanks.