Good question. Put another way, is there ever a possible scenario where the w/l record is beyond the coach's control? The answer is yes and the scenario is very close to what happened to GT this year.
That said, I don't think coach is completely void of responsibility in this year's record. There are probably some things he could have done better. He'd be the best one to ask about that, not the knuckleheads (me being one) on this board.
As far as the OL goes, it did not play well this year, as we all know. However, it is my firm belief that our O is more interconnected and interdependent than most, if not all, other offenses. When one unit struggles, it almost assuredly means the other units will suffer to some degree, as well.
I really think the poor play by our "skill" guys: Bbacks, Abacks, wr's........... all of them, had an accumulatively negative impact on our OL and it's ability to execute assignments. Iow, their job was made significantly HARDER by the incompetence of the skill groups. If "incompetence" is too strong a word, insert inconsistency, if you like.
Maybe the term should be amended to "unskilled" guys until they prove otherwise.