Reddick, Lavarnway, Scutaro, and Salty as the bottom 4 in the lineup is not going to scare anyone. That puts a lot of pressure on the top 5. Ellsbury would have to continue where he left off. Youk would have to stay healthy, and Crawford would need to return to his Tampa days. If one or more of those things don't happen, the offensive performance couldbe very inconsistent. Even if the top 5 produce, the lineup would be considerably weaker with out a high performing Ortiz. When he was out of the lineup last season, the offense flat-lined except for 1 game. I have every reason to believe that pulling Ortiz out of the lineup without a potent replacement would weaken the lineup.
Assuming that Lavarnway can fill Ortiz shoes in 2012 is just not reasonable.