Okay, this is all fascinating. Ummm...kinda strange, but fascinating.
We occasionally make cables at Boulder Amplifiers. We are not the same company as Boulder Cables. We actually haven't the faintest idea who they are.
Our amps, preamps, DACs, etc, were all designed with benign inputs and outputs and were specifically engineered to negate the electrical charactersitics of cables, line conditioners, tiptoes, etc., as much as possible. This is to try to maintain neutrality throughout the audio chain as much as possible. A good high-end system that's engineered and designed towards neutrality should make as much effort as possible to limit the effects of the outside world and tweaks. If you pay that much for a system, the engineers should be taking everything into account for you.
That being said, by all means evaluate every cable you can get your hands on. If you hear a difference and something works better than another for you, go for it. If you don't, then do what's comfy.