you could say the same about any form of communication. some people just don't know how to communicate ideas effectively, whether it is via email, essay, phone

you could say the same about any form of communication. some people just don't know how to communicate ideas effectively, whether it is via email, essay, phone call, conversation, twit, et al. i do my best, when i'm about to communicate an idea in any form, to condense, polish, and qualitatively validate the idea/message/whatever before i actually communicate it, whether that means actually verbally saying the words, or hitting send on the email. not everyone will understand my internal dialog. you have to translate your thoughts into a real-world message before it gets sent. dealing with others that don't? ask questions and take notes if you have to. other than that, you just have to adapt to understanding other people's brain dumps if they can't filter them on their own. look for topic sentences and latch onto them.