The worst (i.e., hardest to interpret) writing I have ever read was written by people with Ph.Ds in English. They can put legal writing to shame any day when they want to.
And these are the people teaching or supervising the teaching of college composition courses.
Of course, I wasn't like that at all when I taught comp - not me, never nope! Of course, I was the master of 90 word sentences there for awhile, though. Comes from reading way too much 18th and 19th century writing, where a paragraph easily and often runs over one page.
My eyes start to glaze over if I have to read any Jane Austen or Thomas Hardy. I love listening to someone else read them on audiotape, but I just can't bear to read them myself!