I know there have been many studies done about the effect of batting orders on success, and many suggest a batting order itself has little impact on wins and losses. That math is far beyond me, but I figured I could look at this in more simple terms. Following is the Tigers' most frequently used lineup in 2009 and the number of times each player led off an inning, in actual numbers and as a percentage of their total plate appearances.
1. Curtis Granderson: 264 (37%)
2. Placido Polanco: 123 (18%)
3. Magglio Ordonez: 89 (17%)
4. Miguel Cabrera: 159 (23%)
5. Carlos Guillen: 73 (23%)
6/7. Brandon Inge: 131 (21%)
8. Gerald Laird: 133 (28%)
9. Adam Everett: 78 (20%)
Granderson, who did not bat No. 1 exclusively, had 130 PAs leading off the game and 134 otherwise as an inning's first batter. The players above represented 72% of Detroit's inning-leadoff PAs.
If nothing else, I think this shows the importance of leadoff hitters is often over-rated because aside from their first PA of the game, they might not lead off an inning with any more frequency than anyone else. Batting order would seem to matter most because players at the top get more PAs over the course of the season than players at the bottom. (No. 1 usually gets about 150 more than No. 9). But simply having a lineup of good hitters is much more important than where they bat in the lineup.