In 2007, the Tigers most often used this lineup:
Granderson (8)
Polanco (4)
Sheffield (dh)
Ordonez (9)
Guillen (6)
Rodriguez (2)
Casey (3)
Monroe (7)
Inge (5)
The Tigers scored 5.47 runs per game last year with that lineup, with due allowance for shuffling in the 7-9 spots and the Sheffield injury. That was good for second in the AL.
The new Tigers lineup will look something like this, having eliminated the weak 7-9 hitters:
Granderson (8)
Renteria (6)
Cabrera (5)
Ordonez (9)
Sheffield (dh)
Guillen (3)
Polanco (4)
Rodriguez (2)
Jones (7)
I plugged in these two lineups into the lineup optimizer at Baseball Musings.com. The '07 lineup is predicted at 5.56 rpg, which is pretty close to the actual 5.47 figure, particularly when you take into account that that particular lineup was used in only 25 of 162 games.
The projected '08 lineup? 6.168 rpg, an increase far in excess of a half run a game.
It translates to nearly 1,000 runs scored. What does that mean when translated to wins? If the pitching staff gives up exactly the same number of runs as last year (797), the Tigers are predicted to win 98 games, a full nine game improvement. That would have won the AL Central this year. In fact, it would have given them the best record in baseball!