Any effect... any 'look' ...used for its own sake... can readily become a cliche.
"when is the right time"

When your photographic vision calls for its use.
So, since I posted this in Portraiture....How do you develop style using these techniques, available to anyone, and set your portraits apart from ten million others without overstepping a precedent of cliché? How do you utilize a variety of techniques, yet still have a continuity of vision? If you shoot a thousand portraits with the same camera, lens, lighting, film, etc. and have pictures that essentially look the same no matter who is in them, Have you achieved a signature "look," or have you failed as an artist? Is this a matter of how one discusses their work?