Sinatra Song Often Strikes Deadly Chord By NORIMITSU ONISHI GENERAL SANTOS, the Philippines — After a day of barbering, Rodolfo Gregorio went to his neighborhood karaoke bar still smelling of talcum powder. Putting aside his glass of Red Horse Extra Strong beer, he grasped a microphone with a habitué’s self-assuredness and briefly stilled the room with the Platters’ “My Prayer.” Next, he belted out crowd-pleasers by Tom Jones and Engelbert Humperdinck. But Mr. Gregorio, 63, a witness to countless fistfights and occasional stabbings erupting from disputes over karaoke singing, did not dare choose one beloved classic: Frank Sinatra’s version of...