Which means...
The only SP help we should be looking for, if any, would have to be better than Mize-Montero-Olson-Flaherty... because we already have those guys and the rotation gets shortened in the playoffs anyways, as you've noted.
We don't "NEED" SP help...
But if the rare opportunity to add a true #2 starter were available, and at a cost that Harris approved... I would not be averse to adding that person. Because the above 4 are pitching like 3/4/5 starters (inconsistent, not reliably dominant, IMO).
I don't know that anyone fitting that description is available anyways, so moot point.
I'm just sayin'...