I dont think that it doesnt matter how much you train your dog.The moment you are out of sight (example upstairs what ever) he will give a natural reaction and if that reaction is attack than there is nothing you can do about it than lock your dog when you are not there. At night when i am a sleep and my sonn comes home and he thinks there is something wrong he will react no matter how much you trained him but this doesnt only count for a co also for other breeds. Can we count on them that they always make the right decision if something is a tread yes or no.I cant even do that myself. You cant ever trust a dog no matter what breed.