I would agree that such a test is a good idea and could certainly be used to detect differences (or not) between different cables or pieces of equipment.

I would prefer much longer term trials to make more meaningful assessments, for the reason I gave above, but there may be some value in a snap judgement.

Tom Fletcher of Nottingham Analogue told me that all of his turntables sounded the same. The difference between the most and the least expensive models was the amount of time you could listen to them without fatigue.