When the season started, there were lots of comments about not having a true #1 and I think that still might be the case, However, they have four guys pitching in the #2-3 range (counting Ober) and Maeda and Varland and Mahle all gave some good starts. The bullpen isn't deep, but when Stewart was healthy, they had three shutdown guys for the end of the game. Hopefully, someone can get healthy or effective (Moran or López) to provide a bit more depth.
I don't know if the Minnesota Twins ever allowed the fewest runs in MLB, but that is where they are right now. It isn't fluky--they have good WHIP, strikeout, walk, and hits numbers--and the club has experienced their share of injuries to the staff.
This is why I do have a little trouble thinking there should be firings. Pitching is supposed to be between 60 and 75 of the game and the Twins pitching has been at the top.