My wildly meaningless prediction is Peterman.
He lost time in the Spring with a dislocated finger. He hasn't really gotten the reps so he was always behind Worley. Worley's inability to separate in the race, especially given the bulk of time he got with the 1s that Peterman didn't, is telling.
Peterman is more mobile.
Peterman doesn't even need to hit the broad side of a barn as long as he can get those "gimme yards" that Jones is referring to.... he's the guy.
Worley didn't show comfortability in the pocket under pressure. He didn't roll out to extend a play. He rushed throws. I think, at this point, Jones is trying to save his mentality. That seam route is the most telling. The receiver (Smith, I think) ran the right route and Worley threw it on time. It arrived at the receiver when he was perfectly positioned inbetween Oregon's Zone. It just got there about 3 feet too high.
So they try the read-option to soften up the defense. Worley can't run that. He's had accuracy issues all year long even at AP when he wasn't even under pressure. The timing isn't there and he doesn't bring an added mobility factor that (from reports) Peterman does.
TL;DR my worthless prediction is that it's peterman