More power for moderate listening levels?

Interesting--lots of commentary here but apparently not by many that own or have experience with Harbeth's. I would suggest you check out the Harbeth user forum. Tons of information there posted by people using many different amps with YOUR speakers. As a former Harbeth owner (and lover) who ran five different amps with my Compact 7s before moving on to another brand and can say this: Harbeth's like--need--power. Each time I put more power in front of my C7's they responded with more jump factor, better dynamics, more projection into the room. You can certainly get good sound with 25 good watts, particularly at low volumes, but if you want to crank them up more power is better. That said, it sounds like you only want to crank them at the occasional dance party and who is listening critically in those instances? 

My 3 year old and 6 year old. 

Your comments are taken to heart. Many folks swear by the difference that power makes. My initial question which is perhaps somewhat naive is whether all that power acts in a way to control the drivers at medium to low listening levels. It’s just sitting there in reserve but can it affect sound quality. I think a few posters here suggest that it can.

@hshifi speaks a bunch of truth here in regards to what constitutes a system for dancing, whether or not you subscribe to the cult of Klipsch or not. When it comes to dance music history there's the Richard Long side, but the Klipsch/Levinson combo is a major crossover for home dancing—the Mancuso/Loft approach, not about "power"—you could do similar with loads of old horn-driven speakers like JBL monitors, Altec, TAD etc... but again, more cults.