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.
At first glance, Maualuga's career-high 122 tackles in 2012 might seem to be cause for significant IDP optimism. That is, until you realize that nearly half of Maualuga's stops were assists, and that he finished just inside the top 50 fantasy linebackers in Fantasy Sharks Default IDP Scoring. You can do worse as depth in large IDP leagues, but frankly you can also likely do much better.