Frewell hasn't played any press coverage with the CBs. They're back 5-8 yards at the snap. Also with the T2 seven man zones, a Bills corner will only be in single coverage if his guy runs a deep flag or out route. Otherwise, on a route toward the center of the field, the receiver gets passed over to the safety (or other back, depending on the package). Together, these factors kind of prevent a CB from showing "shut down" abilities, or, alternatively, the scheme is designed for masking the lack of shut down corners. That said, Fewell may be under some pressure after these years of the bend-then-break, to have his backs take some risks and jump some routes when the occasion presents itself. However, with the time opposing QBs have without getting pressure, I doubt the latter.