In the bowl game loss to BYU his junior year, Josh Allen was 17/32 for 207 yards (6.7 ypa), 2 TD, 2 Int, 55.3 QBR. He ran for 27 yards.
Josh Allen wasn't Josh Allen as a college junior, either.
Retzlaff against Colorado: 12/21 for 151 yards (7.2 ypa), 0 TD, 2 Int, 30.8 QBR. He added 29 yards rushing and BYU blew out Colorado.
A little worse than Allen, but not far off. Better in a couple of categories.
I think the biggest mistake is viewing Retzlaff as a completed product, rather that a work in progress with some really good arm talent and a heart as big as ... dare I say ... Texas.