[Lorenz-Kraft]

I think there are no direct studies about message length and efficiency. You might want to look closer at NLP because most of what you might be looking for is defined within NLP.

For Example: "Efficiency" depends on the sender (who writes) and recipient (who reads). But this is not the end. 1: HOW is something written (Hard to grasp?=> Flesh Analysis) 2: HOW is something written (10 px Font on mobil? => Typography) 3: HOW is something written (light white 20px Font on light grey background?? => Typography and Color Contrast) ... and so on for almost all topics. There are mostly more than one question to be answered ... for both views (sender and receiver).

[utopman]

Thank you for this constructive answer. I understand here that indeed there might have answers in NLP for my question. I also mainly understand that there are no simple answers. It's a very hard question that should be splited in many sub topic to have a true response overview, what looks to me to hard for a proper answer. I think now I have to dig the internet a lot to have a more accurate response ;)

I can elaborate more on my inital question by rephrasing as following : "Does short messages systems (messenger like / sms) in 2020 provide better human communication (more efficent, better comprehension) than legacy long messages systems (emails, letters, books) ?

Rephrasing makes me understand that the question is still way to large as it need a lot of definition ans asumption to hope an simple answer.

[Lorenz-Kraft]

I think the "medium" (twitter/mail/messenger) and its "limitation" do not matter a lot. I think it mostly depends on the sender and the receiver (and its circumstances). If they have a mutual understanding (same "degree") of the message, the communication MIGHT be more efficient due to lessen time delay. Nevertheless, the sender might use the wrong words ... speaking Portuguese ... you see where this leads ... also, and most fascinating ist the "time factor". Like: "Do you need time to understand / grasp something?"

So as I see it: The communication medium itself is almost always not responsible to for "better human communication". BUT, as all rules, there are exceptions, for example, twitter is a medium that can, with one "tweet", move a whole flock of birds at once (I think this was the initial intention of twitter ... philosopical seen). This "reach" (unprecedented before) opens up a whole new slew to "human communication". Like with one tweet: 1: Some Trump might declare war with ($random-country) 2: A Country might revolt (see Arab Spring) 3: Stock Market might break ...

By the way, not sure if you might like it, but "Cognitive Load" is a very interesting topic in itself. Its about your own possibility to grasp/understand/dissect things. Its mainly about "basic" things that, when cumulated, are totally obvious OR totally confusing. In my opinion, this is the main key to "better human communication".

But to end this topic, here is my recent -Word of the Week-: If you can't explain something well, its likely you don't understood it either