I don't seem to have a problem with sighted results, should I?. All of my experiences were sighted except one, where the Benchmark and Stello were compared. We switched cables and inputs so much that I lost track of which DAC was in which input. It didn't matter. Neither of us could tell them apart under meet conditions.
Regarding my sighted experiences, the results were more often than not opposite my expectations, like your Radio Shack cable test.
"Sighted" usually means that you know what you are listening to. That also implies you know when you've switched something, so you have an expectation that something has changed. I think that psychological experiments have demonstrated convincingly that expectation can influence perception so much that you could easily "hallucinate" differences that aren't there.
As you say, these differences were against your conscious expectations, but that is not proof you didn't hallucinate them. People have unconscious expectations too. Or maybe people just have a random first impression when they switch, and then their brain "goes with it". That's what seemed to happen to me in the fourth blind trial I did, where I got the ordering of the 3rd and 4th cables incorrect.
I wish I had references to studies for all this stuff. I tend to remember general impressions from articles I've read in the New York Times science section but I never save the links.