I believe that if you "cast" out your energy, magically or otherwise, and then you cannot let go psychically and proceed to mentally harp on the subject, you will inevitably bring about some sort of reaction. I DO NOT believe that "what goes around comes around"...there are plenty of great and sickening examples right in front of us in the world at large-gross injustices, cruelty to animals, victimization, murder, molestation, etc. If you are an adept enough Chaos (or another flavor, its really quite irrelavant) Magician, you will be able to throw your energy and concentration into a working and then you are done with the matter. Until such time as the results of your workings come about, you have thrown away the remnants of that subject. So, in short, no.