Many times the unity of a team dictates its success.  Your examples are challenging and motivating.  One thing I try to do both personally and with teams to keep the gossip down is make sure the people I'm talking about are in the conversation.  But another one that seems to be a helpful reminder is that if I disagree with someone, I should be talking to them rather than to people with whom I agree.  We are going to have disagreements, but my way of keeping them from becoming divisive is to make sure I keep the communication lines open with those on the other side.  It's too easy to talk to the people who agree with us and divide the group.  We must speak with the people we don't agree with to maintain unity.  Thanks for a great post!