Mike Mulligan at the Chicago Tribune echoes my thoughts on this point:
“[Charles] Tillman isn’t the best cornerback in the NFL, but he’s the best system fit in the league. And he’s an essential playmaker at a position where the Bears are dangerously thin. One longtime NFL scout said Tuesday that the Bears are very thin at cornerback and predicted teams would start to go after Isaiah Frey at nickel back.”
Frey has performed well but he hasn’t been asked to do much. I’ve been wondering why teams haven’t picked on Frey more. I think this might be something to keep an eye on.