scientific double blinded cable test

It can’t be that difficult. Pharmaceuticals are tested that way. Either something works comparing to placebo or not. And the variables are really complicated there. We bring people to the same room with the same high quality sound system, set of recordings and procedures agreed by a venerable audio society. We have our control cable, placebo, something off the shelf. We compare to it other cables with the same L, R, C. We ask testers to judge the sound reproduction accordingly. Neither experimenters nor testers know whether tested cables or control are used. If the results are near 50/50 then we know that if L, R, C are the same, no other variables matter. Pure physics. Bob Carver did it with amps, surely somebody must have checked it with cables? 
Then of course another study could be done how cable  L, R, C influence people’s judgements. And how expensive, or not, is tuning those three parameters.

There are s lot of factors, and I have done Test a with 5-6 in the room and with 
My high quality preamp, amp digital and seperste power dupply and  goid power 
Conditioner.   Never mind $10.
Try a $200  interconnect , speaker cable , snd power cords vs a $1,000
Any credible cable will be easy . K tried blue jeans monster even lower model of same brand,  where I had No idea when switch box was used ,custom built 
All connectors and internal connections the same, plus I owned a store and had many cables to compare to once runin.  Soundstage is bigger deeper imahubg is much more real  as well as image focus and Bass. If you can tell then dome thing 
Is very wrong in your system or you have problems with your  ears.

@geoffkait 

In other words how do you explain cables that measure the exact same L, R, C sound different all things being equal?

Can you give an example of two cable assemblies with the same measured LCR numbers and vastly different sound?

nugat: I ran such a test at AES. For valid results, all participants must have demonstrated the ability to discern subtle variances reliably, or the results will devolve to 50/50, as it did at AES.

It is very difficult to control all the variables. Electronics and speakers vary as they warm up, getting people in the sweet spot, distractions, etc.

Even if everyone agreed that the two differ, it would be difficult to get a consensus of better.

IMO, the best test is in a system well known to the tester. Regardless of the DUT, the whole system should be re-plugged to establish a baseline and re-verified with well known source material. Only then introduce the new component. If there is a difference, it will readily be apparent. It's tougher with power amps to provide them with the same work so they are at the same thermal point.

Only then should the tester say "BananaRama is really good in my system. Check it out and see what it's like in yours." 

 Such a test would need to be performed in an ordinary room  with speakers placed in less than ideal positions as the average listener would have things.  Testing high-grade cables and low-grade cables of equal electrical properties,  Like 2 coathanger’s stretched out compared with whatever high-end cable Of the same conductance. 

To expand on the question? Has there ever been measurable speaker differences with different cables? ETC? Frequency response? Impedance? Has an amplifier ever displayed a different level of distortion using exotic power cables? As in does an amp begin 1% distortion at 100 watts with a stock power cable but managed 105 watts with an upgraded one?