I've asked mr. Thomass how he got this info, this is his answer:
Hello, after several discussions with Yuneec . I don't want to forbid anyone to calibrate its Typhoon H , however, it is just not necessary ! Due to a high error rate when calibrating it seems probably come to some crashes . I myself have repeatedly calibrated , if only the / because of the videos , my could always be carried out properly , so I seem more likely to have a problem with it . As I said, happy again . The copter is a Ready to Fly System unpack , and fly ! ( Statement of Yuneec ) calibration only when the status light turns orange 3x or he drifts ! greeting
Now we need for Yuneec to put that in writing.