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Superfluous: Redundant, unneeded, extra, excess, useless, unproductive, unnecessary, pointless, unwarranted, waste.
If a purchaser should avoid asking for superfluous information, information that's unneeded, extra, excess, useless, unproductive, unnecessary, pointless, unwarranted, why then would superfluous not apply to a patient who practices a method of flossing that his or her dentist deems as being unneeded, extra, excess, useless, unproductive, unnecessary, pointless, unwarranted?