Incorrect. The author is retired FBI Agent, Joe Navarro, [0] an expert on reading and interpreting non-verbal body language. One of the cornerstone of non-verbals, explained in WEBIS, is the comfort/discomfort paradigm. [1],[2]
Is a person comfortable? Why not? Is there a mismatch between verbal communication and non-verbal actions? This is where rapport comes in, the ability to make someone feel at ease and something taught by the FBI when interviewing. They don't "break" people, they charm them by putting them at ease, let them drop their guard and inquire further. The earth shattering point of WEBIS is everybody exhibits these body language responses and I consider it to be a sort of human response API regardless of country, age or sex.
As for eye contact. Hold too little contact and you appear submissive. Too much and you may be signalling to another person you are aggressive.
[0] backgrounder by Octavio Blanco "This former FBI spy hunter fled Cuba at age 9" ~ http://money.cnn.com/2015/10/27/news/economy/joe-navarro-cub...
[1] Navarro, 2007.
[2] read Charles Fifield, "Setting the Sale Through Persuasive Communication" http://www.baylor.edu/business/kellercenter/news.php?action=...