""... Reasons to stay at three founders ..." One reason not to have odd number of founders where n>1 is pair-ups. When people work in groups they tend to pair up and form dyads. Especially when times get tough. This is a very natural and stable work configuration. An odd number of founders means someone is left out. It's no co-incidence the most basic army formation, a brick is 2x2. I'm wondering though, would it hold true for 2 extro and 1 introvert founder?" - Peter Renshaw