After a rookie season in which he captured nine interceptions and a legitimate Pro Bowl berth, Buffalo Bills safety Jairus Byrd "let down" in his second season in the NFL. In 2010, Byrd hauled in just one interception, leading many to believe that Byrd's rookie season was an aberration.
Kirwan has spent his off-season lockout releasing positional rankings in groups of five at a time. Insofar as his safety rankings go, Byrd's name falls under the Group D heading, meaning that Kirwan considers Byrd one of the 20 best safeties in the NFL.
Rankings are meant to be picked apart (seriously, Roman Harper in the Top 10?), and this isn't likely to change every opinion on Byrd. I think Kirwan's right: Byrd has his limitations, but he's a playmaker, and the Bills don't have a lot of those defensively.