Well unfortunately I don't have as much film as what the coaches do so much of what I can suggest is based upon gross assumptions which may or may not be correct.
Firstly, I've heard that players aren't getting all that many extra snaps for the offensive line. This is something I would correct.
Drills should focus on fundamentals - what I'm seeing is that players are off balance and on their heels, being pushed around. Additionally, their hands aren't placed well and they're getting slapped off from the push. Is this a problem with OL strength? It seems they're not really pushed backwards too badly but are always susceptible to stunts and inside moves. Drills should focus on maintaining balance and have the defense practice these stunt and swim moves.
I'd like to bring in Quinn Johnson to see if the running game can be improved. I doubt the loss of one of the fullbacks will significantly worsen our ST play, which in itself is already rather subpar and spotty.
Bring in free agents for try outs at the OL positions.
Watch film on how other teams are able to block so well. Is it because they're stronger? Faster reactions? Better fundamentals?
Doesn't this all sound familiar? Well personally I agree with what the coaches are doing and what they're working on. However, it's not translating on the field. There must be a good reason for it. We need to isolate reasons and correct them. This poor offensive line play has been going on for 2 seasons now. Yet Favre was sacked, what, 12 times in 2007? Players haven't really changed too much. Has playcalling changed? Is Favre that much better at reads? Watch film from 2007 and see what differences are evident.
Basically, go back to first principles. Start from the very start. Prior to the snap. Positioning or hands, fingers, eyes, helmet, body, angle, how spread your legs are, pre-snap looks, pre-snap audibles. Timing of the snap. Reactions by OL players. I've seen videos of boxers being able to punch a punching bag by reacting to a light within 0.3 seconds or something. Have they practice reaction skills of this sort. Practice having their arms thrown off. Practice dropping back while being pushed by a DL. Practice pressing forward while being pushed by a DL. Practice lateral movements. Time how long each OL can hold for. Use incentives. Use negative reinforcement. Perhaps the fact that these players are so young, the occasion of a football game gets to them and they don't perform as in practice. This is alluded to by McCarthy when he said he kept the same schedule even though it was a Monday night game. Pipe in field noise. Bring in crowds. Have direct scrutiny by the coaches breathing down their neck. Practice is not a time to joke around, to have some fun before the games. Practice is where corrections are made and fundamentals addressed. Have them feel the pressure, make it feel like they're playing for their starting spot.
Whatever the case may be. Go back to what makes a good team good, and see where your team differs from that. Then keep practising till your team emulates that. You have to be tough on the players to perform well in all aspects of the game at all times. That's what I'd do before I start firing people.