I once heard a story about Larry Summers’ management style when he was president at Harvard. In faculty meetings Summers would frequently cut off whoever was speaking to say, "So what you're really trying to say is…" Being told "what you’re really saying" can be annoying. Um, no, actually that’s NOT what I’m trying to say.
The challenge with Summers, the story goes, was that most of the time he really did re-phrase their point in clearer and more succinct terms. It really was what they were trying to say. Hence his reputation as a brilliant man but indelicate manager.
I want to stress, per Paul Graham, this story is not just about articulateness. Clear communicating is clear thinking. To be able to describe an idea more clearly than someone else means the idea itself exists more clearly in that person's mind.