I'm not sure they knew how bad it was going to be.....until the week before.
They had to have had some inkling, for sure. Due to the size and youth of the offensive line.
Remember that ominous post someone had about an unusual closed, indoor scrimmage like a week or two before game 1? Where the #1s on offense just couldn't do anything against even the #2s on defense. And the #1 defense was just lights out, it didn't even make sense to continue. Or something like that.
And there was general "sounds like internet tinfoilery" as a response. In hindsight, yah....no. If it happened, they knew, for sure then.
I have little to no ability to judge ability of individual players. Other than maybe QBs, runningbacks, kickers, and maybe a defensive back or linebacker. And that's only basically many games in. How much can they REALLY tell during the runup to the season....or at least the point they are well past running drills, learning the plays, etc.....and are actually attempting to execute what they would have to do in a real game with the personnel that will likely be on the field at that point?
I mean, my only point of reference is Hard Knocks. And I think they have no idea what 70% of the players (who didn't play the previous year) are capable of in a game. In other words, they have to see most players in a game or two (as opposed to my several games) before they know. Maybe they're a little better on those skill type players than I am. RBs/WRs/QBs....etc...and they can tell right away from drills. But how well is your line gonna do? Or your defensive line?