I wonder if it isn't the problem of replacing rotors on the big rigs, seems everyone is always replacing their rotors when they have disc brakes on cars and pickups.
Heat and water are the only dis-advantage that I see to drum brakes, and both can somewhat be avoided if one pays attention.
You can lock up the brakes disc or drum if adjusted right
and thoes big trucks with smokiing brakes coming down the hill are completly out of controll, and it is driver error unless something broke