The play calling was at times very suspect. Usually a couple or three times a game.
However the real culprit was the offensive scheme.
I remember someone once noted that we had a good number of running plays, and we did. Handoffs, counters, dives, pitchouts from all over the backfield. The problem was the vast majority of which ended up in the same place, between the tackles. Defenses just had to sit and wait.
The so called Bubble Screen, it almost never worked because there was never a blocking bubble out in front, so it ended up a "naked" screen.
Our passing offense essentially worked twice.
1. TH's ability to extend plays and 2. DW's remarkable dual threat ability - and NFL or near NFL caliber receivers.
Against better defenses, even TH bogged down because of little or nothing schemed over the middle.
No matter what happens going forward, we are not going to see the above glaring offensive weaknesses under RR.