Look no further than Dante U. Thomas Austin is a sophomore (i.e. year two in the program), Orhnberger a Junior, and Wendell a Senior, and Connolly a fifth year senior.
I assume the thinking is that those guys are good enough, and know the system well enough, to hold down the fort at RG and the backup interior line positions as well or better than some random veterans.
Exactly. Mankins/Neal go down, next one in. Connolly started 13 games and the Pats offense was historically efficient. The schedule was pretty average but had enough challenges to make the results mighty impressive.
Connolly goes down, next one in. In the 2 games the Pats got down to Wendell on the depth chart, they went 2-0 (outscoring 72-10), yielded 1 sack (6 total hits) and ran for 400 yds (4.6 ypc). Obviously the Bills and Fins aren't the best measuring stick, but they are division opponents and they just got spanked. Even Hoyer was able to move the team with ease.
Dante U. is the best and most cost effective way of filling your backup lineman roles. If they develop enough to start when called upon (Neal, Gorin, Ashworth, Hochstein, Connolly), that is a bonus. You can still draft your starters in the top 100...my ideal in 2012 would be:
LT - Solder 1st
LG - Mankins 1st
C - Ben Jones 2nd
RG - Cannon 5th (should have been top 100)
RT - Vollmer 2nd
Connolly, LeVoir, Wendell and Ohrnberger will likely have graduated by then, but Austin (needed to get stronger), Maneri (position convert) and others will take their place. All for minimal salaries. All highly motivated to prove themselves when they get the change. Seems like a solid plan to me.