I have been crewing many a aircraft, with a full complement of C/C whom the only thing asian about them was probably where their ties were made. Certainly there were cabin crew that spoke Japanese and no doubt did their job well, But there were complaints on more than one occasion, and it more boiled down to two different cultures with two different attitudes, fully understandable on a international flight, no matter how hard you try, the human factor comes into it, especially in times of stress like severe turbulence, to say it did not occur is bullSh%t.