FWIW, I never cracked a set of rotors, just billions of spider cracks. I did manage to wear 2 sets down to min thickness.
Wheelhopper and Force4.6 will testify that I did use my brakes as hard as they did, and with more weight behind them (lightweight bastards).
with the same plates as I? If so did you block off part of the airflow so as to cut down some of the air blowing on the rotor face?