The 2003 Red Sox and 2006 Cubs are not similiar. The Red Sox offense was able to overcome the defensive shortcommings on that team (Ramirez & Walker for example). However, Walker was horrible defensively in 2003. IIRC, he was the absolute worst 2B at turning the double play in all the Major Leagues. Undoubtedly, that lack of defensive execution put additional stress on the pitching staff by allowing teams more chances to score. By contrast, the Cubs will rely much more heavily on their pitching and defense in 2006 because their offense doesn't appear to be capable of scoring more than 4 runs a game consistently. Add to that a starting staff that may struggle, collectively, to pitch into the sixth inning because of likely limitations with pitch counts (Wood & Miller) age (Maddux) and stamina (Williams?). IMO, it's the only explanation for why the Cubs are seeking to upgrade Walker at 2B A run scored is equal to a run prevented. Doesn't it make just as much sense to want to improve the already weak offense at the expense of what is already a good defense, compared to greatly downgrading the offense at the expense of defense in a not very important defensive position.