Forgetting memories is a protective consequence in most situations, and it is in direct connection with the life force and identity. Making people forget such lowly and unimportant things is childish and aimless for both parties.
However, magic workings in a direct situation, such as a person making a decision or whatever can manifest in such confusion but only on a temporary basis. One way to implement and also erase thoughts is when the person is asleep and dreaming, programming the subconscious. Or a working to manifest an outcome, the energy can manifest in the mental as such.
Communication and well being between people should be started on a good faith effort, and in emergency situations a cleaning and blessing working works wonders. Another great factor is to take in account the planets.