Gonna call "bullshit" on this one buddy. But a friendly kind of bullshit, since yeah, they (like all pitchers) could all get injured or faceplant. But the case for them is this:
Houck was doing pretty well as a starter in 2023 before the comebacker that hospitalized him. He was uneven in his return, but I'm comfortable chalking that up to the trauma of the event and the recovery. He can still go deeper though, as he has the third time through problem - which is kind of mysterious as it does not seem to be tied to any noticeable fatigue or loss of stuff or location. (From looking at Savant.) I am hoping Bailey is the fix.
Whitlock has been hamstrung by injury. Hipstrung actually. When he came back from his second injury last year he wasn't stretched out and so they yo-yo'd him into the bullpen. But he actually seems more likely, with health and coaching, to be a more viable starter than Houck. Again, fingers crossed for Bailey.
Winckowski is interesting. He lost a year to covid in 2020, and had 1 year of decent AA/AAA starting experience in 21. He was called up as an emergency starter in 2022 and was not great. But he was probably a bit rushed as far as development goes - a year off, then 1 season in the high minors. Over the 2022-3 off-season he revamped almost all his pitches. In 2023 he was put in the pen due to an abundance (heh) of starting arms, and was never quite yo-yo'd into the rotation despite all the comings and goings. He was exceptional as multi-inning reliever early on, then as a single inning reliever later into the season. He's one of those guys who has better stuff now than he did in the minors. It's really again a coaching question in terms of transitioning him to the rotation from the pen. Again, Bailey will have an impact here, but perhaps not the Houck-whispering or the Whitlock-conditioning. So he may be the easiest at the end of the day.
These are not bad arms. They're not even bad pitchers, even though they are not sure things.
What they all have in common is they've never gotten a true, uninjured, full season of starting (except for Winckowski's emergency call up). But that does not mean they can't do it. And we only need 2 of the 3 of them to rise to the occasion. Would I be more comfortable if it were only 1? Sure - absolutely. Would I have preferred healthy 2021 Giolitto in the rotation? Again, yes - absolutely. But this is not yet an abject disaster.
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Murphy I'm agnostic on, and Walter I'm less sanguine about. But I think that out of the Fitts/Criswell/Murphy/Walter group, there might be a ML arm. Even if it's only Murphy as an effective multi-inning lefty out of the pen, like he was in the beginning of '23.