From the LA Times:

"Come late September, Manager Mike Scioscia and pitching coach Mike Butcher will have a difficult decision to make: Which one of the five starters, who have had seasons ranging from very good to superb, will go to the bullpen for the playoffs?

"John Lackey's status as staff ace makes him a lock to start, and Jon Garland's postseason success gives him a decided edge, so the final two spots probably will come down to the three younger pitchers, Santana, Saunders and Weaver."

If you believe in things like WHIP and ERA+, Jon Garland is objectively the worst pitcher on the Angels' staff. If you prefer wins and ERA, he's still in the running. Either way, Garland and Weaver, without question, make up the bottom 40% of this rotation. Garland had one season, in 2005, in which he pitched very well and did his part to anchor a very much overperforming White Sox rotation during their World Series run. However, that is the extent of his postseason success and (I believe) his only postseason experience.

With all other factors (mostly health and stamina) being equal, leaving Garland in the playoff rotation while sending Santana or Saunders to the bullpen is...well almost as stupid as letting Garrett Anderson start a playoff series with only one good eye.