I believe this question is far more complex to answer than the effort being put into the answers I have read. A formal breakdown of position coaches, injury analysis, individual player abilities, play-by-play analsis, game planning for each game, situational analysis compared to play call, and player decision making on a play by play would give you an answer. Without this effort, the answer is so dependent upon your expectations of the talent on our roster.
For example, one could state that the tight ends have technique deficiencies and have underperformed compared to perceived talent. They frequently worsen the blocking situation and the QB decision making. That seems to indicate there is a weakness with the TE position coach.
My answer is I do not know because I am not willing to spend the hours required to give a reasonable answer.