In theory, a Vogelbach/Valencia platoon makes sense. Vogelbach is a skilled rookie, and this team that fancies themselves as contenders needs to protect themselves from having a black hole at first base.
Valencia crushes lefties, slashing .318/.389/.515 against them. His 155 wRC+ against southpaws in 2016 were equivalent to Josh Donaldson. In Layman’s terms: Danny Valencia is as good a hitter as Josh Donaldson against left-handed pitchers.
Vogelbach hit righties more consistently and with more power than he did against lefties. He hit .339/.451/.563 against righties at the Triple-A level in 2016.