i don't think she blocked the cero directly, just the debris that flew around after

What are you talking about? The cero was going directly at her. Also she didn't block it, Ichigo brought out his Hollow powers and blocked it himself to save her. That was kind of the point of the whole scene, Grimmjow put Inoue in danger so that Ichigo would bring out his full power to save her.
i think he was talking about the one that burned grimms arm, at least i was