I'm not sure I totally agree with that. Here are some good tips from the Wiley textbook "How to Master Simulations."
-Express yourself in as few words as possible
-Use a topic sentence at the beginning of each paragraph
-You should not convey information in the form of a table, bullet point list, or other abbreviated presentation.
In addition, I recommend making a very simple outline before you begin writing. Choose your stance on the subject, list what the topics will be for each paragraph, and make sure you know where you're headed before you write yourself into a corner. The 2-3 minutes it will take to do a brief outline is well worth it.
Finally, you are correct that the communication part is not graded for accuracy. However, it does need to be on point to be graded at all.
I would agree with a lot of these points. I have currently passed two sections (working on Audit) and so far have scored fairly well on the written communication by applying these pointers. I think someone could definitely improve their scores with these.
Also, it is definitely worth your time to spend extra effort on the written communication given it is a sizable portion of the graded material. Keep working at it!