Sam Walker didn't start off looking to examine team captains. He started off looking at the most dominant teams - and that led him to his thesis that team captains (a particular type of that breed) are what drives the best teams forward.
First, he had to figure out what were the most dominant teams. He started off casting his net widely, looking at all sorts of team sports from around the world over the last 100 years. He decided to focus on teams that had at least five people in the field of play at all times, and who had a sizable following at least somewhere in the world. That culled a lot. Then he decided it must be clubs that stood alone in their sport (more on that later on), played the highest available competition (so he nixed the Vince Lombardi Packers, because of the AFL-NFL divide, even though the AFL was the inferior league), and had to last at least four years.
Based on this, he was left was 17 clubs. Yeah, there's an NHL team (Montreal Canadians), a baseball teams (Stengel's Yankees), an NFL club (Steel Curtain), and two NBA teams (Spurs and Bill Russell's Celtics). There's also some soccer teams, a handball team, a women's soccer club, a women's volleyball national team, the Soviet hockey team, an Australian rules football squad, a women's field hockey team, and two rugby squads. It's a pretty diverse batch. And Walker says all these teams have one thing in common: they all had the same type of team captain. And Walker argues that team captain wasn't usually the best player on the team, let alone any sort of all-time great. Some are stars (Yogi Berra, Bill Russell, Tim Duncan), but most weren't. One soccer captain was derided as a "water carrier" when he became captain, but he embraced that description.
Walker says the captains had seven common characteristics: 1) they were incredibly dogged and never gave up, 2) they played to the edge of the rules to see how much they could get away with (and that meant taking some occasional fouls), 3) they "led from behind" and led by serving the team instead of themselves (this is where Walker discusses the water-carrier soccer captain), 4) they engaged in practical communication - they were rarely big speech-givers and they generally hated being in the public eye, but they could help facilitate team-wide communication behind closed doors and on the field of play. 5) They were good at non-verbal displays of communication, which is kind of an extension of the previous point, but Walker notes that not all communication is verbal. 6) They were willing to cause some controversy - but only if they saw it as being in the good of the team. If they made any controversial statements, it wasn't about any personal petty issues. And 7) They were good at regulating their emotions.
Everyone of his captains gets profiled in the course, and you can see some general similarities as he does it (though Walker is clearly picking his spots when to profile Captain A or Captain B). And Walker does a good job highlighting a series of studies on psychology, group dynamics, and leadership that back up his points on how people like his captains can help raise the level of play and effort of their teammates so everyone maxes out at their level.
While it is an interesting book with a nice premise, there are some problems. For example, no matter what criteria he uses there will always be some gray areas on the in/out lines for what clubs get selected - but that doesn't mean some of the choices are bewildering. He tries to explain it in an appendix, but it's still bewildering. Why aren't the 1936-39 Yankees in his cut? Well, they didn't win as many consecutive titles as the 1949-53 Yankees. Well, then why are their two different NBA teams involved? The Bill Russell Celtics, sure - but why the Tim Duncan Spurs? Walker says the 1990s Bulls didn't make the cut because of their pair of playoff losses in the mid-1990s, but .....six titles is still more than the Spurs won, and in fewer years. If the Spurs qualify, why not the Tom Brady Patriots? It's a similar record - extended greatness for well over a decade with multiple titles. Really, that Spurs one just messes up a lot of his standards.
Also, his later chapters on the decline of the position of captaincy in modern times really seems a bit like cherry-picking. He notes that the position of captain in the 21st century has become more about giving it to the biggest star, or not having it at all. And money has begun to influence things in pro sports. Ummmm... how are any of those things new? Look at the Yankees- they once had Babe Ruth as their captain. They were also captain-less for over 30 years during some of their best years ever. (Walker calls Yogi Berra the captain of the Stengel Yankees, in a frankly arbitrary decision). Money's influence isn't new. It sounds like he's holding up all modern captains to the standards of the best captains in history, ignoring that there were always some inferior captains - that's now new.
He has a nice chapter at the end going over flawed captains. He has an interesting extended critical take on Michael Jordan, who Walker sees as NOT what a leader should be like. He argues that Jordan was all about Jordan, which explains why he often belittled his teammates, how they didn't become a dynasty until Bill Cartwright was named co-captain (and Cartwright was both a guy who had stood up to Jordan, and had been nicknamed "Teach" for his willingness to help young players). Also, Walker argues that Jordan's weird mid-career retirement shows how he doesn't fit the mold. He was just an adrenelin junkie who always wanted to prove himself in competition, but he'd already proven himself in basketball so he left his team. Walker makes an interesting case, though he does overdue it. (As self-centered as Jordan is/was, he was willing to feed John Paxson with the ball at key points in the 1991 finals and Steve Kerr in '97).
In general, it's a very interesting book. Added bonus: it even has a glowing blurb from Theo Epstein on the back cover.