Morally, I think that every spell should be used with caution and care as to when and where it is called for. There are some really bad spells and the fact that they exist is scary, but they should be know to all who might encouter them. So that a counter spell can be intreduced or if needed to use the orginal to defend yourself, only if nessicary. But then that is why there is a school and family to teach young ones the difference and the dangers in casting spells.