LAS VEGAS – Sometimes it pays off to watch tape on your opponents. When Melissa Gatto struck Tamires Vidal in the left breast, the reaction may have seemed delayed and unusual to the outside observer. But Gatto (9-2-2 MMA, 3-2 UFC) was well studied. She’d seen Vidal (7-3 MMA 1-2 UFC) do the exact same thing before, pounced for the finish, and won by TKO. “No, of course (I wasn’t surprised) because I watched the last fights of her,” Gatto told MMA Junkie and other reporters at a post-fight news conference. “Always she felt that