That move was arguably the last straw needed to move veteran Willie Colon from right tackle to left guard. The plan was to fill the right guard position with DeCastro, overhauling an interior offensive line that took much of the blame for many of the team's shortcomings in 2011.
Heading into Week 15, not only have the Steelers lost all of the benefits of those moves, but they may end the season worse off at those positions than they started.
Colon missed the Steelers' Week 12 and 13 games with a knee injury, and he re-aggravated that injury by the second quarter of the Steelers' 34-24 loss to San Diego in Week 14.
It appears now Colon may be lost for the year, the third time in three seasons Colon will be placed on injured reserve. DeCastro has seen very limited reps on special teams just a few weeks after coming off injured reserve/recall. He suffered a major knee injury in the Steelers' third preseason game in August.
The Steelers have played through Colon's injury by moving center Maurkice Pouncey to left guard and inserting Doug Legursky at center. Not only does that move the Steelers' best offensive lineman to a position at which he clearly is not comfortable (judging by his performance in the last two games), it puts lesser-talented Legursky on the field.
During Colon's time out, the Steelers have rushed for 191 yards on 52 carries (3.6 yards per carry), but the running backs have rushed for 87 yards on 31 carries (2.8 yards per carry).
Options are limited, and while they won't likely include moving RG Ramon Foster to the left side and plugging in DeCastro on the right, it appears as if an interior line that was supposed to be significantly upgraded this offseason will limp to a finish in 2012 - whether that's in the playoffs or after Week 17 remains to be seen.