I think that Atwell's book speaks to this basic idea. There is much in way of evidence to suggest that a difficulty in writing is generated from the premise that thought is not clear. When there is a lack of thought being generated, writing is not going to materialize. Thinkers like Atwell make it clear that writing is rooted in the basic processes of thought. The more thought that one has in terms of being able to process and visualize these ideas, the better one's writing is going to be as it comes from a place where there is something to be articulated. Some of the major challenges seen in writing, student writing in particular, is that the thoughts are not clear and when these are not clear or in focus, the writing will follow suit. From an epistemological point of view, we write our thoughts. The ideas we think and are articulated in our mind help to drive our writing. When these are absent, the writing suffers and the writing becomes absent. I think that this goes far in suggesting that there is a clear link between the difficulty in writing residing in the difficulty in thinking.