I just listened to that concert today and i never noticed the so much screaming by the japanese girls before. Of course between tracks and also when Roger sings or something special on stage happens. But in this show i noticed that in Liar they really scream LIAR everytime Freddie sings it. Crazy!
Good observation. It was like that at most of the early Japanese shows. It's beyond me why they didn't bring the song back in Japan 79 when it was such a crowd favourite. They brought it back in Europe 82, but that was the exact wrong time and place to do it..