I got the opposite experience. People with good technical skills often write dense, skip explaination of topics that they find easy to grasp, assuming the reader also find them easy (which usually is not the case).
I used to do this too - write dense essays and documentation that took forever to read. Then I took a class on business writing at my local university. It was well worth the time. It helped me focus on writing short, terse language that was simple and quick for the reader. If your organization does struggle with producing easy, well written communications I would highly encourage considering they enroll in some sort of 12-week long course with an experienced instructor who can provide direct feedback.
Eh - I find those people are often the same ones who write weirdly dense pythonic one-liners (cause less lines == good), don't write documentation for their code (cause all code they write == self-documenting), and assume that their interpretation of the English language is standard (even though it's often enough not their native language).