And if the big ego is stubborn consensus remains blocked. The process is stymied eternally. Consensus is based on privileging minority rights over majority rights. It is fundamentally conservative - drastically favoring things as they are over change. If 99 people in a 100 member group want to change something, that 1 person out of 100 who is against in can "block consensus" essentially excercising a veto power.
And - quoting what comes next out of order, because I think the above was the more important point to address:
> Why can't a neighborhood group using consensus send a delegate to a city-wide group using consensus which then sends a delegate to a regional group that uses consensus?
Imagine this process in New York city - lets say ending up with forty delegates. Forty New Yorkers meet in a room to represent New York - in all of its' diversity of people and opinions. If forty New Yorkers, truly representing NYC, reach a consensus about anything - something has gone terribly, horribly, tragically wrong