Yes, write short.
This is the title of one of the chapters in “Writing without bullshit”, hilariously followed by the first paragraph: “Use fewer words”.
Other tips from the book:
* Edit everything
* Aim for a word count
* Say what you really mean
* Start boldly
* Organize relentlessly
* Prune sections and arguments
* Use bullets or tables
* Use graphics
* Trim connective tissue
* Delete weasel-words and qualifiers