Your link led me to this interesting article: a "voodoo audiophile" conducted a (not quite double) blind listening test of power cords (with predictable "hit ratio" of 49%). The artice is surprisingly honest, given the author's "bent" (he did try, in a rather charming way, to discredit the whole idea of objective testing and measurement). The most interesting part to me are quotes from other chap, a "skeptic", who essentially says "'high end' power cords and 'CD demagnetizers', of course, do nothing; but, if you feel you enjoy your systems more using them, by all means go for it!". There is a very thin line between a placebo provider and a fraud...