CB: It wasn't a superheroic Monday night for WBTV's competing DC Comics shows, and the pair sharing a timeslot on competing networks may be working some negative magic for both at this point. Supergirl in its third week continues to garner great reviews for CBS, but dropped a huge half a point, from 2.2 to 1.7 rating. That also meant a total viewers drop from 8.9 million to 8.17 million. The show debuted at a 3.2, and while that was clearly unsustainable, a nearly 50% drop is cause for (mild) concern. If it levels off in this range, though, it should be in good shape.