Visualization and day dreaming are similar in a lot of ways. Both can be harmful if over done, and both can really help you focus on the goal you have in mind, and have your subconscious mind figure out ways to make it happen in reality.
Most times people look at day dreaming as a bad thing or what lazy people do, but I tell you many really great men go out to quiet places and sit for hours day dreaming of their idea and how to bring it to fruition. Very similar to visualization, their merits and demerits depends on how you use them. You give a knife to someone, he may use it to do something useful or he could use it to kill himself. Thanks for coming around!