One of my mantras about writing is that writing is thinking. Writing is simultaneously the expression and the exploration of an idea1. As we write, we are trying to capture an idea on the page, but in the act of that attempted capture, it’s likely (and even desirable) that the idea will change.
While I read the whole piece, I find this is the main point. Time and time again, Warner mentions "writing is thinking," even in his other pieces of writing. Writing is changing, our ideas are changing, and that can take us to what we want to convey. "But the point I’m trying to make here is that all of this thinking matters even if it’s only experienced by me." We reach our goals when we start thinking about our writing, elaborating, and getting to where we want to go. It's a process.