I brought up yesterday that the Phillies may be happy that the Red Sox are sending the ALCS back to Tampa for a sixth game. My point on the Phillies was that it gives them a chance to set up Hamels for Game 1 and that it means their opponent (presumably Tampa) will have at least one more game in which to risk injury or tire out their pitchers. However, Steve and Angie threw down the gauntlet in yesterday's comments section by bringing up the 2007 Colorado Rockies and 2006 Detroit Tigers as examples of teams that had a long wait between the LCS and the Word Series and lost.
So, thanks to the vast amount of information at baseball-reference.com -- one of the three best sites on the internets, along with IMDB and Wikipedia -- I was able to do a quick analysis to see if this is really the case. Does a longer wait hurt a team going into the World Series? I looked at the postseasons since 1995, the Wild Card era, and calculated the days wait for the winner of each league, the regular season wins by each league champion, and the number of World Series wins by the team that had the longer wait. You can find the chart here.
True, the '07 Rockies and the '06 Tigers had the longest wait differences at six and five games, respectively, and both lost. However, the three other teams who had wait differences longer than one day -- the 2005 White Sox, 1996 Yankees, and 1995 Braves -- all won. Besides the Rockies and Tigers, only one other team with a longer wait of any length lost, the 2000 Mets. You can't even take into account which team was better, using regular season wins, as three out of the five teams with fewer regular season wins and wait differences longer than one day won (and, weirdly, eight out of the thirteen World Champions had lesser regular season records).
Bottom line: There's no correlation, no proof that a team gets rusty with a longer wait. It sounds good, but doesn't bear out in practice.