To summarize: extraverted teams led by extraverted leaders tend to be ineffective because everyone’s too busy talking to listen to each other, while introverted teams led by introverted leaders tend to be ineffective because no one wants to say anything. The authors argue that introverted teams benefit from extraverted leaders and vice versa.
In my professional career, which started in 1978 at John Hancock (a large insurance company), and then a small entrepreneurial start up company, Delta Dental Plan of Massachusetts in 1985 which at that time was just starting on its own (disengaging from BCBSMA), and then at Northeast Delta Dental in 1995 (a medium size, financially solid but not well known) — in all three of these different companies, each with its own unique corporate culture, I have found that situational leadership was/is the key, and the use of Myers-Briggs when establishing teams was/is all important. In other words, you want to balance teams with introverts and extroverts for optimal effectiveness, and use of Myers-Briggs types is an excellent tool to help you in formulating teams. You want to balance analytical types who want to think about a problem for a while with high closing people (SJs in the Myers Briggs lexicon). Insurance companies historically are filled with employees who want to move “the paper or the claims” real fast, and fewer people with great analytical skills. But we know to be successful, you need both types of employees. And in today’s world of insurance and health care reform, analytical employees are becoming more and more important to the enterprise. Similarly, as leaders, you need to be situational — for example, when you are in the middle of a systems conversion, you may rely on more extraverted and high closing leaders to be responsible for the project; conversely, if you are strategizing about the next generation benefits product to compete in the new world of Exchanges emanating from Health Care Reform, you may want to have several analytical and introverted people in the group, perhaps led by an extraverted leader who is out there in the market, but a leader who will not rush a product to market without doing customer due diligence. In short, leadership and teams — like a lot of things in life and business — requires a balance.