IMO, there are several breeds that are quite capable of maiming and killing their victim. I only base that on my father's plastic surgery practice. His patients were almost exclusively attacked by Rottweilers and Dobie's.They were the bred 'attack" dogs of that time.I agree there are many breeds involved in attacks/bites/aggressive behaviors. How many of those breeds will take the attack further to maime/kill their victim? This is what we need to concentrate on.
I blame the owner's not the dogs.