Speaker cables from same brand as interconnects?

Many of the fellow audiophiles say in one's system speakers cables should be from the same brand as the interconnects. In my opinion this is not often the case. It is true that many cable brands have their own "house sound", so certain sonic characterics apply for both the interconnects and speaker cables. But one has to realize that they should have other properties as well as they are meant to carry different kind of electrical signals (voltage based vs current based electrical signals). In my case I'm using Cardas Golden Reference speaker cables and pure silver interconnect cables (Wireworld Gold Eclipse) because I feel these are the strategic places these cables can offer the most sonic benefit. I think the same theory holds true for power cords and digital interconnects. What do you think?

Chris