Can someone explain to me the idea behind batting a pitcher 8th instead of 9th? I realize that this is basically meaningless for the Phillies, as their #9 hitters are about as effective as the pitchers at the plate, but I can think of a number of reasons why you would NOT do this.
1) 5-6-7 in the lineup are more likely to be on base or in scoring position than 6-7-8, so wouldn't you want an actual hitter coming up in the #8 spot as opposed to #9? This has happened several times this year to the Phillies, including yesterday when Hellickson (8-spot) came up with the bases loaded and 1 out.
2) In the NL, a pitcher is often asked to sacrifice bunt. After a sac bunt, it's more likely that the #1 hitter will drive in the run than the #9 hitter.
3) Over a season, the #8 spot will come to the plate more often than the #9 spot. (Just like the #1 spot will come to the plate more often than the #2 spot.) This reason isn't all that significant because the 2 spots are right next to each other, but I would lean towards maximizing plate appearances for actual hitters as opposed to pitchers.
4) Maybe the reason is that you want guys on base for the leadoff hitter. I see a couple problems with that. First, the pitcher is still hitting #8, so you're still seeing that automatic out very close to when the leadoff hitter will bat. Second, the bottom of the Phillies lineup is terrible and is extremely unlikely to get on base anyway. Third, if you are that intent on getting guys on base for your leadoff hitter (and THAT confident in your #9 hitter getting on base), then why isn't your #9 hitter just batting leadoff? Move your leadoff hitter down in the lineup if you think he is a run producer.