Writing skills are very important in the business world. I worked at two major companies, DuPont and Phillips Petroleum, and at both I attended short courses in business communications. The primary focus in those courses, and in this posting, was on letters and short status reports.
The course at DuPont stressed getting to the point quickly. The subject and its importance to the primary addressee were to be stated in the first few sentences of a letter. To follow up on our progress after attending the course, some managers would use a stopwatch to time how long it took to know the subject and the purpose of our letters. I don't recall their goal, but it was something like 5 seconds.
The course at Phillips focused on selling...ideas, products, projects, etc. This course actually addressed both written and verbal communications. The main point was to first present the proposal's benefits to the decision maker, followed by the adverse effects of not buying or approving the proposal. Finally, the benefits could be repeated at the end to help close the deal.
I thought both courses were excellent and I tried to apply the recommendations throughout my career.
Do letters (i.e. paper, snail mail versions) even exist anymore? Email largely replaced them about 20 years ago. Even with email, the recommendations from the courses still would apply. But what about Twitter? The limited length should solve the time constraint. Oops, the length is limited, but content may still be a problem. Don't fire the HR training staff yet!