Since I am a chromatographer, (and can separate and analyze complex mixtures) does this give me any insight into what a certain vodka might taste like? No. Will I tell you that two vodkas taste alike because I cannot measure the difference between them? No. If I measure a difference between two vodkas, will I tell you that you can therefore taste a difference between them? No.
Maybe I am misunderstanding you. Let's say I have two vodka samples and run a GC-MS with good resolution. And the two vodka samples have identical peaks. That is, they contain exactly the same chemicals in the exact same proportions (i.e., you cannot measure the difference). Let's set aside for a moment that this is doubtless the same vodka from the same batch. It is not clear to me how these can actually taste different. Yes, the perception of taste may be different, or the variables affecting taste may be different (e.g., eating a sardine beforehand vs. eating a chocolate). If you are into perceived benefits, suggest you look at products by Peter Belt (who is at least honest enough to admit that's what he sells) or Machina Dynamica (who is not).
Moving back to wires, I think that it is a reasonable hypothesis that 2 wires manufactuerd by the same company from the same run in the same lengths will "sound" the same. By "sound" I mean any direct effect of the wire on the sound coming out of the speakers, or any indirect effect the wire may have on active components in the system resulting in an effect on the sound coming out of the speakers. I am not talking about perceived sound.
OK? Identical wires sound identical? Next, what real material characteristics can change the behaviour of a wire (assuming all external variables are identical). My short list of main variables are RCL. There are likely others, such as the much vaunted "skin effect" and crystal structure. But it is exceedingly difficult to see how these can manifest sufficient change to audibly alter engine performance, except as these variables are manifested as RCL. Speaker drivers are really best thought of as very simple, inefficient electric engines whose performance is based on EMF. They don't care about the pain and suffering electrons have passed through in getting to the wires in the driver; all they care about is that the electron moves through the wire and generates an electromagnetic field. So, there is no reason to believe that there is any characteristic other than RCL with the potential for a change in the sound. If people feel that there is something else, they should be prepared to demonstrate it; i.e., the burden of proof is on the proponent of a new hypothesis.
So wires with identical RCL should perform identically in an audio system. Changes in RCL "may" have an audible effect. (Not power cords, by the way, unless the power supply is poorly designed and/or poorly executed. An obvious example would be RCL way beyond the bounds of common sense, like a 500 ft 18 guage power cord.) All of these variables, and their direct effect on signal, can be measured. Their indirect effect, like high capacitance wires blowing unstable amps is an unknown, but it is probably not unreasonable to assume that minor changes will have negligible effects in well designed well executed equipment. Note that it is impossible to uniquely assign this effect to a wire, since it is the combination of a wire and specific pieces of equipment. Note also that such wires seem to be pushing the boundaries of good engineering.
There is little doubt that wires can change the sound of an audio system, though this probably decreases to the extent the componets are properly engineered and manufactured. The question is whether, within a relatively generous RCL range these changes are audible, and if so, whether the change is "better, "worse" or just plain old "different". The answers, I think, are "exceedingly unlikely" and "different".