but i agree, messing around with spirits wheather it be for good or bad use, its very dangerous. besides what good witchcraft could you possibly be doing that is safe?., be that act as hosts for these things are only opening up thier minds to all kinds of spirits.
and to my knowledge, "good" spirits, arent always as good as they seem, if they were, why are they still around.
as far as evil spirits goes, they'd do anything to appeal to the human world, for example pretend to a family member. that is pretty much the ultimate in evil.(they are just doing what they're good at)