I dont quite agree with everything you said there to be honest
It is quite true they will attack the dead or dieing, but if something living is damaged or has a wound you can count that as fair game as well. While they would not only attack when protecting babies, in fact the young fend for themselves. The natives sure do swim with the piranhas, but for only as long as it is not the dry season and they have no wounds. Not trying to be Mr Right there, just wanted to make some correction bud.