Popularity is not a proof
Let's not forget that among the most convincing people out there are con artists and psychopaths. They have gotten all this "why you should trust me" stuff down to a fine art. As business manager or recruiter, you have to ask yourself what your hiring priorities are. If you only want someone who can look and sound the part, then the above advice is all you need.
This assertion is not supported by the research. I refer you once again to Hunter & Schmidt's 1998 meta-analysis of the factors behind workplace success. When organizations are persistently recruiting for this kind of fluff instead of what the literature actually shows, no wonder hiring is such a hit-and-miss affair!
"Working to improve your body language has a profound effect on your emotional intelligence." Really now! Look at Stephen Hawking, who by the way has a disability, and we all know he is very emotional in his talks, down to earth and very intelligent. Maybe you should listen to one of his lectures. What about Helen Keller? Ludwig van Beethoven? Ray Charles? Stevie Wonder? And on and on I could go. YOU CAN BET THEIR BODY LANGUAGE HAD NOTHING TO DO WITH THEIR INTELLIGENCE. "Studies show that people who use positive body language are more likable, competent, persuasive, and emotionally intelligent." I take this statement as one who does not use, nor have positive body language skills, are less than all others, how unfair. Think about all those who are disabled! "Learning to use positive body language will make people like you and trust you more." HOW CRUEL. Wow! Again I say think of all those who are disabled.
For the sake of balance, I'd like to point out that there was a (much larger and more powerful) failed replication of the power pose: http://datacolada.org/wp-content/uploads/2015/05/5110-Ranehill-Dreber-Johannesson-Leiberg-Sul-Weber-PS-2015-Assessing-the-robustness-of-power-posing-no-effect-on-hormones-and-risk-rolerance-in-a-large-sample-of-men-and-women.pdf There was also an analysis of the original study and they suggest that the first result was likely a false-positive (they found a result by chance, rather than because of their manipulation):http://datacolada.org/2015/05/08/37-power-posing-reassessing-the-evidence-behind-the-most-popular-ted-talk/ IQ is a very robust and well established concept whereas the evidence for power-posing is very weak. I'm therefore sceptical about the ability of body language to "trump" IQ. Also EQ is a contentious concept at best.