have you seen our olinemen ? theyre fukking maulers, and our WRs and TEs block as well as anyone in the league
One factor that is likely impacting the lack of success on downfield throws is the 49ers' faltering run blocking.
This part of the offense fared very well during the first half of the season, as San Francisco's run-blockers posted a 52.8 percent good blocking rate (GBR) during that time frame.
GBR measures how often a team gives its ball carriers good blocking (which is very roughly defined as when the offense does not allow the defense to do anything to disrupt a rush attempt). To put that 52.8 percent GBR into perspective, it is just more than 3 percentage points higher than the league-leading 49.6 percent GBR posted by Minnesota in 2011.
The issue for the 49ers is their run blocking hasn't been anywhere near as good over the past eight weeks, as the team's GBR during those contests fell to a 44.9 percent level. That number gets even worse if the measurement is limited to the Week 11-17 contests in which San Francisco managed to post a 43.1 percent GBR.
A big part of the problem here is Davis, as he is one of the worst run blocking tight ends in the league.
The number of mistakes he makes in this area are overwhelming but not limited to his being the master of the very ineffective push block, not finishing his blocks well and sometimes putting his head down when initiating a block. This last item is physically dangerous and has the side benefit of not allowing him to see how to react to where the defender is moving. Davis also looks like he does not want to initiate contact with defenders and that trait may explain a lot of the aforementioned technical issues.
Fullback Bruce Miller is much better than Davis in his willingness to get after a defender but he gets overpowered at the point of attack so often that he really can't be counted on to lead runners through the line of scrimmage. This is almost certainly why the 49ers have been rotating defensive and offensive linemen into the backfield at the fullback position but it really hasn't helped that much since those linemen have not displayed the requisite ability to read the line of scrimmage with a running back's eye. For them it is usually run upfield and hit the first defender who shows up and that often isn't the highest percentage move for the run play called.
Add in the fact guards Mike Iupati and Alex Boone and center Jonathan Goodwin have all seen significant declines in their run blocking over the past eight weeks and it indicates this isn't a matter of just picking up the pace in the backfield and edge blockers.