Lost in the conversation about whether the Phillies should actually go forward with their double platoon idea in the outfield is how it will affect the bench. Using four players to fill two spots will hamper Charlie Manuel's late-game decision-making and could limit what the Phils do situationally.
As explained in detail over at CSNPhilly, the Phillies won't be able to simply play two guys per game in the outfield corners. If Darin Ruf and John Mayberry start against a lefthanded pitcher, the Phils will need someone to replace Ruf defensively. The only options as of now are Laynce Nix (an average defender), and Domonic Brown (a poor defender).
Or what about when Nix and Brown start against a righty? Once a lefty specialist enters, Nix and his .183 career batting average against southpaws will exit. That means that Mayberry, in 70 percent of games since that's how many righthanders tend to start, will have his role defined. Manuel won't be able to use Mayberry prior to the LOOGY's entrance, unless he is OK with pinch-hitting for Nix with Ruf and leaving Ruf in the game defensively.
It ties Manuel's hands situationally, where he has never been among the game's stronger managers. Adding a guy like Scott Hairston would change things altogether, because you'd have two potential defensive replacements and it would add a powerful bat off the bench.
Right now, that fifth bench spot is still up for grabs. If you pencil in spots for the two outfielders who don't start, the backup catcher and either Kevin Frandsen or Freddy Galvis, that leaves room for one more player. There is no need to have both Frandsen and Galvis on the active roster to start the year. If the Phils value Frandsen's offense from their utility role, he should stay. If they value Galvis' defense and ability to play short, he should stay. But keeping both up to start the season doesn't serve a purpose. And Galvis could use further offensiev development in Triple A; he was thrust into a big-league role because of Chase Utley's knee injury.
Ender Inciarte? The Rule 5 pick from the Diamondbacks has to be offered back to Arizona if he doesn't make the Phils' roster, but he's never played above Single A and is a longshot to stick by Opening Day.
Double platoon or not, the Phillies need another bat. Unless you're comfortable heading into a season hoping for the best-case scenario from two non-regulars and two question marks, and knowing it will limit Manuel's options late in games.