When I read computer science papers, I often find them written in a rigid, academic style compared to a blog post or a book. I sometimes skip reading papers for that reason. This is sad — there's all this human knowledge that was painstakingly discovered that readers are skipping because it was poorly presented.
One good writing technique is to take a complex idea, simplify it by eliminating some details, and present the simplified version. Then, once readers have understood that, present the details that you left out.
Maybe academics are afraid that someone will take the earlier sentences out of context and claim they're "wrong". When I was in college, my advisor picked out such an introductory sentence and said that I should be more accurate. I explained that it's just a simplification and that the details he's worried about are in the next para. He said, "That's fine, but this sentence should be correct by itself." The earlier sentence was wrong only if one picks nits. Actually, it was simplified, not wrong.
I wonder if academics don't understand or respect (enough) the principles of good writing.