That's a very good point! Ok then ideally the "experiment" would first measure with some type of multi-meter or of electronic equipement and then a real world test with the various connections to verify if any difference is heard or measured with a microphone/analyzer.
There was a hdmi cable test done like this a while back. They used some fancy electronics to measure the capacity of various (length and company) cables and then performed real world tests. On paper, a few hdmi cables that measured less than ideal, where still able to pass the signal from source to monitor. That study is what turned me onto monoprice and steered me away from monster for my cable needs.
I think measuring (equipement and ear) the speaker connections would be a insightful test. In then end most likely no difference would be found, but one never knows until proven otherwise.