I think it takes time in the development of the O-Line. Remember, in Houck's second year there was a different OC calling the plays (not a very good one either).
Even though it was widely reported that we kept the same play book after Linehan left, there were still different tendencies and tweaked terminologies to overcome.
Also, Mularkey's offense was very predictable most of the time (even the trick plays), which played into the fact that the other team's defense was able to figure out quickly, the plays being called which made it hard for the O-line to block for that called play.
I believe that this season will work out better for them if not only for the reason that we should have a less predictable offense.