"Close Doesn't Always Count in Winning Games" by Benedict Carey (New York Times, 3/7/05):

[S]ocial scientists who have studied group performance under pressure say that often it is decentralized groups (like the Yankees) that prove more resilient than strongly connected ones (like the Red Sox); they are better able to weather outside criticism and internal quarrels.

Evidence from personality profiles and from studies of military, corporate and space flight crews suggests that looser ties between group members can be a strength, if the team includes individuals who can generate collective emotion when needed. And the Yankees have several of them.

Some other key points:

-- "Winning is more likely to create team unity than vice versa, Torre has said repeatedly, and the evidence backs him up, said Dr. Richard Moreland, a professor of psychology and management at the University of Pittsburgh."

-- "When a common purpose is shared, loosely tied groups can function better than strongly bonded ones when it comes to containing dissent or bickering, research suggests." It allows individuals to withdraw from squabbles without disrupting the group's work.

-- "On a tightly knit team, by contrast, a falling out between key members can divide a squad, forcing people to take sides, psychologists say."

-- "Whether such independent, loosely tied people ultimately succeed as a unit depends not only on strong management, researchers say, but on the presence of individual group members who can circulate through disparate parts of the team, reduce conflict and help generate collective spirit when it is needed."