the second time through the order ops+ against is high, the third time it's REALLY high. Houck stuff is really good, but with only two pitches most batters have him figured out the 3rd time through if not the 2nd.
He'd actually be fine as a 4th 5th type in todays game, but this rotation has a TON of 4th and 5th guys already. I think hi starting is a backup plan depending on how the offseason looks, if he's starting with Whitlock it means they didn't add anyone or only one guy. With that in mind, and the need for both starting and relief pitching, I certainly hope Houck is in the pen next year.