I dont mean to sound like a broken record here, but you continue to completely dismiss that the "back up plan" was injured too. Barnes can and has played Guard. So has Barrett Jones. That they didn't use them, should only exaggerate the point that they just weren't available. Mike Person was the #10 man on the depth chart and he was pushed into duty due to all of the injuries.
Just run down the list of players who ended up on the injured list at one point or another: Scott Wells (lime disease, elbow injury); Barrett Jones (back surgery); Tim Barnes (pinched nerved, shoulder injury, bruised ribs); Demetrius Rhaney (knee injury - IR); Jake Long (ACL - IR) Rodger Saffold (shoulder injury); Mike Person (shoulder); Brandon Washington (missed 3 weeks in training camp).
You reference the Vermiel Offensive lines. You want to know what they had more than anything else? Continuity that comes from guys remaining healthy. I challenge you to name the backups on those GSOT teams. We all remember guys like Nutten, Gruttudaria, Tucker and later McCollum, because they stayed on the field. So to say this can compare to that just isn't fair.