Fair point, but that's not about writing vs. speaking, but one's approach to writing. I wrote a blog post, years ago now, that included the following:
"The Internet is littered with long defunct, three-post blogs in large part because blogging is generally viewed as writing, and therefore every blog must apparently carry the burden of high school English classes: What's my thesis? Have I developed my arguments? Spelling counts! Jeez, haven't I written 500 words yet?" [smr.absono.us
Seems like what you're asking is what approach will let people write without it feeling like "writing," while still guiding them towards creating something that is intelligible to other people.
Almost an outline that's developed by a group...