Anecdotal proof that argument mapping helps with essay writing

Bali-based educationalist and teacher trainer Steve Bolton has been getting results with Rationale.  He writes:

Finally some proof that argument mapping works. My current class have been reeling off fantastic essays after planning them using argument maps. Here we can see low and high tech versions. Today a student handed me a six-page (A4) map of an essay, and while I am clueless about Novi’s field of study, I can follow her reasoning with ease. Exciting stuff!

My emphasis.

We already know that argument mapping improves critical thinking [pdf].  Of course seeing the results in one's own classroom must be extremely gratifying.