Questions of Good Thought and PTL's Syllabus

Recently I looked over the syllabus for this class. One sentence struck me and I was hoping to bring it to the attention of the class and see what we think. The line that strikes me is, "good thinkers are good writers (and vice versa)," (found under the Q+A's and Weblog section of our syllabus). This seems to adopt a narrow view of 'good thinking', and it seems worthy of exploration. Ability to articulate one's ideas in a written form was not one of the traits discussed in our break down of critical thinking and good reasoning, however that certainly doesn't mean it is not. Yet, it seems that making good writing a necessary qualification of a  good thinker takes a limiting view of intelligence, in which non written skills aren't as highly valued. I am, however, inclined to agree with the idea of the good writer as a necessarily good thinker. I hope to hear some responses from the class and professor, perhaps I'm reading too far into the claim, or not being charitable enough.