I suspect that both Magico and Luxman demo with quite expensive cables, Luxman makes very expensive reference interconnect and speaker cables, by the way.
I don't think Mike wants to go to a great length to choose cables, that's why I didn't suggest complicated approaches.
He also says that the power in his area is bad and unstable. This may have nothing to do with the choice of speaker cables but one should do something about it. I think, in the beginning he underestimated a little the cost and effort that are involved in achieving good sound.
Yes, very wrong cables can screw up the sound big time, regardless of how good active components are.