Chuck, welcome. What the brand K dealer said confused two entirely different points, as John B. indicated. The Ks are more efficient in the use of amplifier power than most speakers, so for a given sound level they use less watts. This isn't really that much of an advantage however, because these days clean amp power is cheap and plentiful and should rarely be a major factor in a speaker decision.
The clarity of a speaker at moderate(or any)sound levels depends on factors such as the flatness of the frequency response, relatively low distortion, good transient response, etc., but isn't related to efficiency.
