Wow all the comments here seem negative. The guy is just saying that people should be clearer with their writing and getting to the point right away to avoid confusion. If they're writing about a topic that's more complex, sure, the writing will need to be more complex. But there's nothing wrong with communicating simply if the subject allows it.
Say you're writing a memo to your boss explaining why you need to double the size of your engineering team. That point has to come first. Now, maybe the reason you need to double the size of your engineering team is that management wants to add new product lines, and customers are demanding more customized solutions. Okay, so each of those points are the leads in their own paragraphs.
Where a lot of people have problems is that their writing is a chronological recounting of their thinking about the issue. So it starts somewhere in the middle where they encountered some part of the overall issue, then backs up to where they recognize the larger issue, and then buries the solution at the end.
The structure you were taught in high-school: topic sentence, supporting sentences, conclusion, is simple and appropriate for business communications. There are some writers who can clearly convey complicated thoughts using a more narrative structure, but you'll rarely go astray sticking to that basic style.