Strength of schedule is calculated from the opponents projected fantasy points allowed for the LB position. The best rating is +16 which gives the player the advantage against the defense and indicates an easy opponent, the worst rating is -16 which gives the defense the advantage and indicates a tough opponent.
When IDP kooks start gushing about linebackers, odds are very few will mention Paul Posluszny, despite the fact that he's logged five straight 100+ tackle seasons and two IDP LB1 finishes over the past three years. The seventh-year veteran's LB5 finish last year might represent his ceiling, but "Poz" is a high-floor fantasy option on a defense that will be on the field a LOT in 2013. You could do worse for your fantasy LB1, especially if you wait a bit before taking one.