I don't think AD has been incredibly impressive at OLB.  He had that awesome sack of Favre and Jones, but his two super bowl sacks were both on the Giants' game winning drive and in both Eli managed to nearly get back to the line of scrimmage.  TBC and Woods have both proven adequate at OLB in our system, but I don't think Bruschi or Guyton are adequate at ILB on 1st and 2nd down.   We get the most talent on the field by putting Thomas inside.  That takes a lot of the run-stopping pressure off of Mayo and frees him up to defend the pass and rush the passer.  It also makes it impossible for the enemy to run up the middle, and even though we're weaker on the edge with TBC and Woods, Mayo and Thomas have the speed to get to the side quickly on stretch plays.   

                             Springs
                                                              Merriweather

                                       Mayo        Thomas
 Wheatley                                                                             Bodden
                     TBC  Seymour      Wilfork        Warren   Woods