It happens. The Pigskins used super-burner Darrell Green to return punts when they really needed a big return. He was awesome at it (see vid below), but he also got hurt doing it (see vid below).
I'm ok with use Cobb for a few weeks, but I'd be working Janis every day to get him ready to do it ASAP.
Anyway, enjoy Green's brilliance and the Bears's futility: