I missed Walker was possibly hurt. Listen, Turnbull was probably always going to regress or get hurt, but at the time it seemed like they not only stopped his momentum but made getting hurt more like due to the back-and-forth (his injury finally happened when he actually returned to the rotation). Walker is probably still a safer bet, based on his track record, than Turnbull. Just not necessarily to be a better pitcher than Ranger.
The question is really just, do you go six-man or do you bury Walker again until needed (as 8th reliever) or (much less likely this early in the season) do you move Ranger to the pen.
All kidding aside, they put Romano in an 11-4 game because he hadn't pitched in three days. While Strahm performed in the same context and Romano didn't I still don't think you read too much into it. Incredibly the Phillies also have yet to lose a game because of him (they won his one blown save).
The other thing is this team's salary structure is such that they can't easilyl release someone like they did Merrifield or Familia in the past, unless they are already to go over the next threshold (which they will if they have to, I'd hope. But not yet).