He's entered Pache for defense and then lifted him when his turn came around at the plate three times now (I think), so I imagine he has thought it through.
The upside is it gets multiple innings of Pache's defense late-ish in the game. I assume he sees Pache as, say, a 9.5 out there, while Robert is more of a 7.8.
The downside is it uses two guys to replace one.