Editing is not like taking puzzle pieces and putting together a pre ordained picture. It is more like taking bricks and making a house, or a palette of colors and painting a picture, or a list of ingredients and making a pie. I think good editors work like authors. They understand that there are really only a certain amount of letters but they can form all kinds of words into many sentences which make up paragraphs that fill chapters and complete books. Knowing this helps one focus on sections of the piece without becoming frantic about the gaping holes still left in the whole. You just work on assembling lively parts And then you join them together. The more seamless these transitions are, the more pace and energy grows. This is where editing becomes creative. Because you cannot just make paragraphs and then place them anywhere throughout the pages. You must structure them just as you did the words which formed sentences. And in order to do this you must have a definite arch, a storyline, a plot. Something that tells the subconscious where this is all going, behind the aesthetics of light and color and music. Beyond the infinite complexities of art there must be a simple cue telling us where we are going. Even in mysteries we are 'told' what the characters are going to look for next. And the biggest mistake is to attempt to make it complex / interesting / pretentious. Because life is complex enough we need stories to be ultimately simple. In editing it is the art of subtlety that must be exercised. Imagine the audience as a dog(not to be demeaning although in a way we are attempting to make the story idiot-proof). You want this dog to go from point A to point B so you place a dog biscuit at intervals along the path. The dog can always see where the next one is and where it is leading him. if you were to hide one in a mailbox the dog would be lost trying to find it. To the point of not even knowing that it exists being completely unaware of it. Or let us say that at some point you begin pelting the dog with biscuits. Surly the dog wants to eat them but is struggling to survive the barrage of input. As editors we must always keep the subconscious mind aware that it needs to keep going. And although your favorite movies may mislead you by this tactic, it is an art where the rules must be learned before you can break them. Another common mistake while cutting is showing the client an early draft. Never let them see it. You don't give your teacher a paper with blank pages in the middle. You wait till you have a complete, even though rough, piece. You don't want someone to see the pie half done. They will lose all respect for the masterpiece. Like a magician halfway through his trick explaining how it is being done. It loses that special magic.