I agree with your post and would like to add that I have been told to look for cables that exhibit low capacitance and inductance.
I believe that the capacitance issue is more critical with interconnects because of the low signal levels at this stage. I cannot say how significant it is because I believe this would depend on the equipment used.
I wonder how much of this perceived difference people claim to hear between cables is due to high capacitance issues between their equipment. For example, a possible mismatch between input and output impedances between a CD player, preamp and power amp.
Another issue that could add to this problem is long interconnect runs. I have discussed equipment issues with many people and have discovered that some setups place monoblock amplifiers close to speakers to minimize speaker cable runs. However, the interconnect must then be longer then the speaker cable in order to reach the amplifier. If the interconnect is high capacitance, and there are impedance mismatches, this may create an audible difference.
I would welcome input from those who claim the differences are obvious. What test methodology was used? What speaker cables/interconnects were involved in the test? Details would at least give me something to go by and help me with my tests.
I did get some input from someone in this forum that differences are not easy to distinguish with a simple blind A/B test. It requires a more lengthy time period for differences to become evident. Perhaps a longer A/B test methodology could be used.
I also ran across a post where someone claims that he has done many A/B tests and his friends have attempted to try and fool him with different cables. He claims a 90% accuracy rate in distinguishing between cables. Thats very good.
I would be interested in what differences he picks up on and his test methodology. I would also like to know if he finds that a correlation exists between price and performance.
I researched some different cable manufacturers products and would be interested in doing a comparison between the Nordost line, DH labs interconnects, and a standard pair of radioshack speaker wire.
I read on the Nordost website about there approach to cable design and they seem to be research oriented in their designs. The only conflicting issues that they stated in their literature had to to with wire shapes. Essentially they state that the nordost 2 flat speaker cable is rectangular in shape because this improves capacitance and inductance over round wires. However, their higher line cables are solid round mult-stranded litz designs due to the improved skin effect of this design.
Very unusual to promote one design philosophy as better, but then to use the worse one for higher product lines.
DH labs has an interesting dielectric material with their air matrix interconnects. They claim a closer dielectric constant with that of air due to the unique construction of this teflon based dielectric. At least worth investigating.
It would be interesting to put these products to the test.