Kendrick is the better choice in LF for the playoffs. If you play Werth just because he makes more money than Roger Dorn or for nostalgia's sake you're making a mistake.
Kendrick is faster, healthier, plays better defense, and at this point in his career/this season.. hits better.
No, you've misidentified the weak link. Werth in LF, Harp in CF, Kendrick in RF.