If Carr plays Sunday this could be the turning point for the O-line
Here's another point about assessing the O-line. Sure, guys get beat in one-one matchups, but so much also depends on everyone on the o-line being on the same page. A guy may whiff on a block, but was someone else supposed to chip or provide help? Z-blocking schemes also rely on a lot of working together as a group.
So the problem goes beyond just not winning one-on-one matchups, it's also working in sync and getting in rhythm. It hasn't helped, too that the QBs have looked for chunk plays--I suspect pushing the ball downfield was an off-season emphasis, but put simply, the O-line has not held up enough to get more of those plays.
PC needs to disprove the doubters by scheming better to get the ball out faster to the playmakers. Marrone needs to coach these guys up on their techniques better.
Put simply, there are a lot of problems too clean up, and it's not one one person or group.