All true, but why not give him the rest of this season to be the full time DH?
Like you, I don't want to see him get called up and get 5-6 AB per week, if we give him another shot, it needs to be full time. Everything you said though is true and reasonable. I can go that route too, however, what washed up bat will we add next off season to be our DH instead of giving Keston a go? If we don't give him another shot next season at the latest, then he just needs to be traded.