Pocket shape and size are an important aspect of pass protect blocking, and those were way below average the first 5 games.
It was also not a great sign that we had one OL that had such a great disparity between his run blocking and pass blocking skills that you could correctly guess the default play call preference for the series just by his presence on or off the line.

There was a lot of improvement in the OL over the last half of the season, which was a positive sign, but regardless of talent level, there is a reason why OL's need time to "gel" and there are things that go on with blocking that most fans have no idea what they are seeing in regards to the OL being on the same page as a unit. Just because a few of the lineman may make it to the NFL, doesn't absolve them from the poor performances that were happening in blocking that were going on and its affect on the offense in the final result.

Koroma, whom I regard as the best lineman was especially out of sync in regards to assignments the first several games with the left side of the line slide stepping which was creating gaps that were very problematic for the offense, yeah he was destroying the guy in front of him, but he was leaving 2-3 yard gaps for stunts and blitzes. There were also lots of assignment mistakes going on, which typically come from the pre-snap calls from the center in WC offenses.

I am all for giving the OL props for their improvement of the course of the season, but they also deserve to take the well deserved lumps for their performance and its affect on the offense for the first part of the season as well.