it's not about figuring out if Vargas is a regular. As you say, we know he's a veteran backup. it is about putting Kieboom and Alu in a position for success and it's about whether the pitchers benefit from better D. On both of those, Vargas is OK playing for a few more weeks.
We're not going to get them a better position than against pitchers with ERAs over 7. This crap is just as dumb as continuing to play Dickerson