[Austroturf]

Someone else mentioned it so I looked it up, and Costello hasn't yet won a road game. Partly that's because he's barely played on the road, his only real game last year was @WSU, which was a tough one. But it's another reason to be nervous. Last year our home/away split was enormous, so let's hope we remember how to travel.

This is true.  But as you mention, Costello only had one true road game as a starter; and other factors (most notably play-calling) conspired to neuter his debut as Stanford's new QB (after Chryst's near disaster in Corvallis).  The other two losses are unfortunate, but have little to do with venue.  USC had Darnold and probably was the better team in the Pac-12 championship.  Levi's stadium had little to do with the outcome.  

And the Alamo Bowl.  This one still stings.  Here, it was the defense that cratered during the second half.  Yes, the last series with Costello under center was a disaster; and there were a few other instances in which Costello failed to deliver (like when he oversaw Parkinson alone in the endzone and threw to Kaden Smith in double coverage); but otherwise, his performance was fine.  For some bizarre reason, Stanford teams do not shine in road venues (except the Rose Bowl); but I don't think Costello can be implicated in this trend.

[Austroturf]

Someone else mentioned it so I looked it up, and Costello hasn't yet won a road game. Partly that's because he's barely played on the road, his only real game last year was @WSU, which was a tough one. But it's another reason to be nervous. Last year our home/away split was enormous, so let's hope we remember how to travel.

This is true.  But as you mention, Costello only had one true road game as a starter; and other factors (most notably play-calling) conspired to neuter his debut as Stanford's new QB (after Chryst's near disaster in Corvallis).  The other two losses are unfortunate, but have little to do with venue.  USC had Darnold and probably was the better team in the Pac-12 championship.  Levi's stadium had little to do with the outcome.  

And the Alamo Bowl.  This one still stings.  Here, it was the defense that cratered during the second half.  Yes, the last series with Costello under center was a disaster; and there were a few other instances in which Costello failed to deliver (like when he oversaw Parkinson alone in the endzone and threw to Kaden Smith in double coverage); but otherwise, his performance was fine.  For some bizarre reason, Stanford teams do not shine in road venues (except the Rose Bowl); but I don't think Costello can be implicated in this trend.