Actually, CLARITY and detailing has more dependency on lower Noise floor or higher signal to noise ratio, so your signals don't get muddled even at low volumes and you can hear every nuance and detail that can easily be modulated and lost by noise. It has more dependency on the amp's damping factor, so that the higher it is, it can control the low frequency excursions of your woofer so as not to crowd out the musical details at low frequencies. It has more to do with higher Slew Rate and smaller Rise Times, so the signals, expecially the highs, rise and follow their peak waveforms as fast as they should, ensuring integrity and accuracy of the source signal's amplication. It has more dependency on smaller Intermodulation distortion and harmonic distortion products, so the signals don't get confused and crowded with extraneous signals that were not in the source. It also has more dependency on having the widest possible bandwidth, so you hear more of the subtleties and airness often found with the highs and the deep lows. Lastly, it also has dependency on better interchannel separation, reducing bleedthrough that ensures more separation and, thus, greater clarity for each channel as each would have their own set of frequencies to handle, and not be bothered with other frequencies form other channels to further increase IM needlessly.
Without any of the above, even the most powerul amp+speakers will not sound clear and will in fact drive you out of the room within a few minutes. Having a generous power reserve will simply enable these qualities to shine through in larger rooms with enough heardroom to guarantee you won't ever have to contend with clipping distortions. But in small rooms, even modestly powered 10 watt amps can sound as crystal clear as long as they meet the above qualities.
Admittedly some of the finest qualities mentioned above can mostly be found in really high powered separate amlifiers like Brystons, Krells, Musical Fidelity, Aragons, Parasounds, Theta Dreadnaughts, etc. And if you're coming from PC systems or HTIB and entry level systems, it is easy to be impressed with higher powered gears. That's essentially because these mid-priced gears often have immensely better technical specs, apart from having greater power. Just my thoughts.