A lot of what happened last year wasn't the OL's fault.
I said last year - a few others did too - that Gurley is suspect. A lot of the lack of production was on him. That's bad news because maybe he's not all that...
Same with Goff. I was one of the biggest trade up and draft Goff advocates. I first proposed that idea in January. But a lot of what happened with him was his fault. That's clearly seen in the difference between his performance and Keenums behind the same OL. That's bad news. Hopefully for him that just means that he wasn't ready and not that he's gonna be a failure.
And then you have the fact that pretty much everyone's performance across the board on offense declined. On one hand that's bad news. On the other, it's good news. A broad declination of performance across a whole unit/team/organization usually points to a broad based issue such as scheme or leadership, not individuals. Since the leadership and scheme have changed there is hope that the problem has been rooted out. Very good news.
IMO, all of these things combined to make the OL function at a level that was less than what it was capable of and look worse than it actually is. So there's good news...