I lifted the following quote from the blog of Tetman Callis who very graciously attributed it, I am assuming correctly. Now all I want to do is read about why they posited this and what are the statistics and the control group, and what were they searching for when they did the study and has it been proven and when does it apply. Certainly not to the written word which means it probably only is applicable or even useful if you are a lawyer arguing in court, or maybe President Obama.
"We hear communications experts telling us time and again about things like the ‘7-38-55 rule,’ first posited in 1971 by UCLA psychology professor Albert Mehrabian: 55 percent of what you convey when you speak comes from your body language, 38 percent from the tone of your voice, and a paltry 7 percent from the words you choose. Yet it’s that 7 percent that can and will be held against you in a court of law.” — Brian Christian, The Most Human Human