Magic fields might be useful for some magic users, but for most of them they are very annoying, if not even downright dangerous. So if passage is needed through an area that is blocked by a magic field, regardless of its nature, then this spell comes really in handy. Casting it will dissipate the field for the conjurer, freeing the way. Needless to say that this spell should always be ready in dungeons and caves, which are notorious for their magic fields.