[Goose]

Quarterbacks are the only position that you really don't know until they play games.  The fact they can't be hit in practice is a very big deal.  Some guys play great when they can't get hit and stink when they can.  Others don't play well until in real games, and some are just great in practice and games.

Both Andrew Luck and Sam Darnold received rave reviews about what they did in practices during their redshirt years.  So nothing they did in games as RS Frosh really was all that surprising to anyone.

I do agree that quarterback evaluation is even more difficult based only on practices than it is for other positions, not just because of no contact (although that is a factor). However, I do not at all agree it is the only position where game performance often differs from practice performance. We have all heard of examples of receivers who catch the ball well in practice and do not in games. Similarly, some running backs fumble a lot in games and don't in practice.
One big problem with evaluation of the OL in practice is that you are playing against your scout team, or, at best, your defense. Stanford doesn't have the personnel to simulate U$C's defensive line. What works in practice may not work in a game. It can also be that the trade-offs matter. There may be a lineman that wins the physical battle against Stanford's DL 100% of the time, but against U$C, he never does. There may be another guy that is high risk, high reward. Against Stanford's DL, he only wins the battle 80% of the time, but against U$C he wins it 50% of the time. In practice, the first guy would be a better choice, but in the game, he is a disaster. The second guy would get a better result, but you don't know that until you play the game. You would have to rely on experience and intuition to make such a choice given only the practice data. Tucker may be an example of a lineman who looked good in practice but didn't get good results in games.

Nobody is saying that Darnold didn't look good in practice. However, the U$C coach decided to start Browne. Was it a bad decision? I don't know, but it could be that Browne looked better in practice but froze up in games. It may have been a good decision that had to be revised in light of the outcome (new data).

[Goose]

Quarterbacks are the only position that you really don't know until they play games.  The fact they can't be hit in practice is a very big deal.  Some guys play great when they can't get hit and stink when they can.  Others don't play well until in real games, and some are just great in practice and games.

Both Andrew Luck and Sam Darnold received rave reviews about what they did in practices during their redshirt years.  So nothing they did in games as RS Frosh really was all that surprising to anyone.

I do agree that quarterback evaluation is even more difficult based only on practices than it is for other positions, not just because of no contact (although that is a factor). However, I do not at all agree it is the only position where game performance often differs from practice performance. We have all heard of examples of receivers who catch the ball well in practice and do not in games. Similarly, some running backs fumble a lot in games and don't in practice.
One big problem with evaluation of the OL in practice is that you are playing against your scout team, or, at best, your defense. Stanford doesn't have the personnel to simulate U$C's defensive line. What works in practice may not work in a game. It can also be that the trade-offs matter. There may be a lineman that wins the physical battle against Stanford's DL 100% of the time, but against U$C, he never does. There may be another guy that is high risk, high reward. Against Stanford's DL, he only wins the battle 80% of the time, but against U$C he wins it 50% of the time. In practice, the first guy would be a better choice, but in the game, he is a disaster. The second guy would get a better result, but you don't know that until you play the game. You would have to rely on experience and intuition to make such a choice given only the practice data. Tucker may be an example of a lineman who looked good in practice but didn't get good results in games.

Nobody is saying that Darnold didn't look good in practice. However, the U$C coach decided to start Browne. Was it a bad decision? I don't know, but it could be that Browne looked better in practice but froze up in games. It may have been a good decision that had to be revised in light of the outcome (new data).