Personally, I think the reason they didn't draft a LT this year was because they felt they had potential on the roster already in Bell (and honestly, all you get from the draft is potential) and he would be manning the blind side at some point in the future. I think the Walker move was meant to be temporary, as he did an adequate job filling in last year. When the time is right, Walker moves back to RT and they figure out the rest of the pieces by how they're playing at the time. I don't think he was ever meant to be the long term solution at LT, and his apparent ambivalence about the move to me makes this scenario more likely.