I know that lineup position has largely been proven to not profoundly impact runs scored, but in some lineups the 7,8,9,1 is Park, Castro, Buxton, Dozier. I think that the opposition would rather not deploy a LOOGY to get Castro out in that case when they could save them for Kepler, Mauer, Rosario. Surrounding Castro with LHH would only increase his PA vs LHP.