This is exacerbated when you pull starters the second time through the lineup and commit to 3 or 4 relievers per game. I'd be curious to see the numbers from 5 years ago or so compared to today. It just seems to me that if you don't have consistency out of the pen, one of those relievers will turn out "not to have it" for at least 3 batters.
Because Whitlock has a recent history (this season) of being a multiple inning relief ace, unlike, say, Hill. And with a sluggish offense featuring several possible season-long black holes, close games will abound, and having a relief ace will convert more of those close games into wins. Especially a high K relief ace who can strand runners.
Also, just from a logical point of view, this is not a one-size-fits-all situation. Generally, it's true that you want your best pitchers to be starters, with the idea that they can go deep into games keeping scoring low, while allowing your team to score. But that assumes a competent bullpen.
- So, posit a club with 5 Kershaws who can only go 8 innings, and a bullpen full of Plaweckis. That team loses a lot of games. Convert that to 4 Kershaw starters and a Kershaw in relief who can go every other day when needed, and they're a much better club.
- Now posit a club with 5 Kershaws that can only go through the line-up twice or not get out of the 5th due to pitch counts (call them Houcks). With a bullpen of Plaweckis, that team loses all of its games.
But no one builds a club like that because it's obvious you need effective pitching across 9 innings to win games.
Here, the question is the tradeoff between having another good starter, and having a bullpen that can convert deliberately short starts.
Again, if Barnes was Good Barnes, it's a different equation. This begs the question: if Barnes
was Good Barnes, should we advocate for a "twice through the lineup" rotation of Eovaldi, Macha, Whitlock, Houck, and Barnes? With a bullpen of something like Robles, Davis, Sawamura, Brasier, Diekman, Pivetta, Crawford, and Hill?
I think that would be insane.