I did not have time to write you a short letter, so I wrote you a long one instead.-Samuel Johnson
Too often, I write letters or briefs without thinking enough about the content of my message. If you know what your message is, great. If not, think about it until you can put it in one sentence, and use the rest of your letter or brief to explain your ideas- briefly. It will take longer, but your writing will be more persuasive and more forceful.