It's a truism among statistically-minded baseball fans that managers don't matter, or that they matter so little as to have almost no appreciable effect on how a team performs over the long season. To be more precise, it's easy to see that a manager can make a lot of bad decisions that may contribute to his team's losses (bunting, falling in love with the hit-and-run, giving speedsters with poor baserunning skills the green light, abusing middle relievers until their arms fall off from overuse, not having a quick enough hook, having too quick a hook, playing Matt LeCroy at catcher [did Frank write the book on bad managerial tendencies?]), but it's hard to quantify exactly what a manager contributes to a winning team. We say the hitters are seeing the ball well and the pitchers are dominating because we can see the home runs or the strikeouts, but we never say the guy in the dugout is managing a great game because we can't see what he adds.
Complicating the process of discerning just what it is a manager does on a winning team is the fact that "great" managers have also been subpar managers. Winner Joe Torre of the Yankees and Dodgers is also loser Joe Torre of the Mets and Braves. The Old Perfesser, Casey Stengel of the Yankees is also the Old Dunce of the Dodgers, Braves, and Mets. Twice World Series winner Terry Francona of the Red Sox is also idiot Terry Francona of the Phillies. The winningest managers seem to win almost wherever they go, are able to even the score by managing for decades, or happened to own the team they managed, but the story for most managers is more mixed, with a few winning teams sprinkled in amongst a majority of losing teams.
In some cases, the same guy who was wrong for one team will find success with another. It's apparent that Manny Acta was the wrong guy for this team. That's not to say that firing Acta and appointing Jim Riggleman is the reason for the Nats' recent winning, but to pin it all on some sort of instant regression to the mean is an exercise in willful blindness. When a manager is fired mid-season, oftentimes the interim manager is someone whose management tendencies are the opposite of the fired manager. The laid back replaces the fiery, the relative stranger replaces the guy who got a little too chummy with his some of his players. It's not clear that's the case with Acta and Riggleman, but it's clear something is different in the clubhouse.
For all the talk that the players never quit on Acta, it seems that the players either really did quit on Acta or felt Acta quit on them. To be sure, some of the players' praise for Interim Jim is a case of coming to bury Acta, but it can't all be ascribed to revisionist history and the fun of winning. Whether it's providing more feedback and being more vocal in general or inspiring the players to a greater sense of accountability, it's hard to say that something isn't different.
Praising a manger for his intangible contributions isn't the same as praising David Eckstein for being a gritty little scrapper who gets things started. The scrappiness of a player like David Eckstein or Reggie Willits or Craig Counsell is a net negative because any potential intangible scrappiness contribution is outweighed by the fact that these people are not very good at baseball and are taking the roster spot of someone better at tangible things like hitting or fielding. However, a lot of what we talk about when we talk about what makes a good manager comes down to intangibles like communication, setting the tone in the clubhouse, and people skills. The few acknowledged field geniuses aside, a good manager is really just a not-obviously-bad manager who does just enough to create a work atmosphere that allows his players to attempt to realize their potential on the field.
Does this mean Interim Jim should be made Permanent Jim? Probably not. Just because the players are happy with Riggleman and they've won some games since he was elevated doesn't mean that the Nats' recent success is due entirely to post-game meetings and ass-slaps and seeing their skipper get tossed from a game. Ultimately, these wins shouldn't have any bearing on who the manger is in 2010. I can argue that the players are happier under Riggleman and that this happiness has contributed in some way to the Nats' recent win streak, but the only thing that seems certain is that Acta wasn't working out. Just because Riggleman is not-Acta, that doesn't mean there's not a better not-Acta out there.