A second pair of eyes
It is always a good idea to have someone else proofread your work. All of us as we write tend to see what we intended to be written on paper and our brains fill in the missing words or thoughts. As a result, words are missing, misplaced or the thought has not accurately been completed. A novice reader to your work brings a free pair of eyes and someone who is reading your work trying to follow your argument/statement. If it isn't clear then they will not get it. Even if you re-read your work and think..."How could they not understand this...?" It doesn't matter that you think it is clear. The point is that you can run the risk with the admissions officer not getting your point either so making a more simple or clearer argument would be highly recommended. It can be challenging and tedious work but I guarantee you that you will be much happier with the end result and it will only bring your closer to your goal of successful admission to that institution!