Ok now we have your opinion. Which ever way you go, the way the Twins did, or the way you suggest, you could end up with at bats that don't have the platoon advantage. If you ask me it doesn't really matter either way and would just come down to players. Who is that lefty that is available in the pen? Which batter are you talking out or putting in? I agree with @stringer bell's idea, they could've put in Kepler and just left him there. Problem solved.
IMO @Hubie29's complaint is just that a complaint, and not very nuanced.