Over the past year of writing professionally, I have learned when to write dumber. If I'm struggling to articulate a thesis or finish a section of an essay, I will simplify the point I am trying to make until I reach a first draft.
Not only does this make the writing process quicker, the resulting piece usually ends up better than my original (complicated) vision.
One reason this trick works because it gets me quicker from writing to learn toward writing to communicate.
When I am first writing a piece, I am usually writing to learn. I need to figure out what I want to say, so I hack my way through thickets of facts and examples until I understand enough to reach a thesis. Thickets aren't usually easy to read, however, so I have to refine those first drafts into a coherent and compelling essay.
The simpler my initial attempt, the quicker I can more reach the refinement stage. And a simpler story likely lays the foundation to add complexity back in if it's necessary.
Writing "dumb" also helps me be humble enough to write for the reader. My readers almost always know less than me about the topic at hand. What may seem simple or obvious to me is often new to others.
By reminding myself to keep my writing as simple as possible, I raise the likelihood that I say something useful to other people.