If you put a ton of pressure on a QB I don't give a sheet who he is he's gonna lose the game. If the opposing defense overtakes your OL then it's all over but the shouting. Of course most times if you have a bad OL then you're unlikely to get a sniff at the SB.Ya I'm over last yr's SB being the case study everyone points to for OL importance. That only proves you can't have 4 starters out and be a total disaster.
You need a competency threshold but otherwise it's seemed to mostly not matter all that much who the elite QBs have in front of them a lot of times. When Marrone was in Buffalo he Miami & the Jets all had nasty DLs and it didn't amount to squat.