You said he has had 5 bad games. He hasn't. I never said the games against OU and OSU were great games by him, or even good games. I said they weren't bad games. He wasn't awful in those games.
And you're right - the outcome isn't just based on QB play. How many dropped passes? How many missed blocks contributed to Jake's turnovers? How many missed tackles allowing the other team to get first downs and additional points?
Take the last drive of regulation against OSU after they took the lead with 53 seconds left. Jake was only 4 for 8 on that drive, yet it was enough to get us in position for a tying field goal. You would dismiss that as "only 50% completion percentage".