I can't remember if it was Hawkblogger or Fieldgulls, but they had an interesting theory:
Maxwell covers the slot. If Simon gets better and better, and seriously pushes Maxwell for time, then it would be best to get him on the field as much as possible. Simon is better suited to the outside (I'm guessing this assumption is based on Simon's physical measurables, although he has VERY good hips for his size and speed), so they slide Maxwell inside.
Keep in mind, Maxwell beat Lane out a while back for the slot WR when Thurmond moved outside to cover for Browner. Maxwell did great in the slot and that set the ground work for where he is now.
So, it's possible that we see Sherman and Maxwell in 2 WR sets, then Sherman, Simon on the outsides with Maxwell sliding inside to cover the slot.
So we'd have 6'3", 6'3" and 6'1" on the field as CBs. Sick.