I had to jump in once more: mitch2 made a note-worthy comment about the role of capacitors in an amp or pre. They are there to satisfy demand for peak power in highly dynamic musical passages. The quicker they respond the better - and the more they cost: here, high cost directly translates into audio quality.
Many contributions seem to try relativizing the role of what they call "science" in assessing effects of audiophile fuses, going so far as to claim we don't even understand the "true" nature of electricity. Well, as far as every-day electricity is concerned, I think Maxwell gave us everything we need to make accurate predictions (which is what science is about). Yes, on the quantum level we might still be in the modeling phase, but that degree of granularity bears most probably no influence on the audio experience. I mean, even the LHC in Geneva uses the same basic electricity and electro-engineering principles, all the way to superconductivity. Now, room-temperature superconductivity might indeed breed a new and better generation of audio equipment, but just not yet. And no, I won't be using liquid Helium anytime soon to fire up my audio gear. As for all matters in life the same tenet holds for scientific claims: extraordinary claims warrant extraordinary evidence! The audiophile experience should not be a religion, lest we fall into the trap of "believe" vs. "evidence". My original question should have been more focused perhaps: "Can anyone in this esteemed forum share experiences - good or bad - with so-called audiophile fuses?" Formulating my question in this way should exclude theorizing on either side of the opinion-spectrum, namely dogma without supporting or damaging evidence. And to satisfy this demand, we do not even have to resort to Einstein or Maxwell, or Lord Kelvin with his infamous statement about human flight. No, we just have to sit down and listen: do we enjoy what we hear? Do we enjoy it more after exchanging one fuse for another? Do we perhaps hear new things in a familiar recording? It's really simple, actually, and quite down-to-earth. But it requires ear-wax removal - in the literal and metaphorical sense - to lead to accurate and valid and reproducible results. That's the only information I was after when posting my original question. Only AFTER we have the data from these experiences - hopefully with more users having similar experiences (moving towards statistical relevance here), should we begin to make sense of our observations, and perhaps even formulate a new hypothesis trying to explain what we observed that cannot be accurately explained by existing theories. That's how science works, not the other way around.