And while clever visual elisions can be effective in the right place, if your story is about a woman who's killing people with the fanged phallus in her underarm it would be a ridiculous distraction not to show the hideous thing at least a little.
Special effects are only another technique, and like any other can be well or badly employed.
But there's a family of special effects which is always bad, which can't ever be used right because they don't have a right way of use. These can be known as extra-special effects . They are alien intrusions. But to be a really good ad for its marketing it needs a further non-relationship, which is why the OOH is there. Extra-special effects have the opposite function.