While I'm very much in favor of making sure a system gets set up properly (isolating power cables from interconnects, using cables with reasonable build quality and shielding where appropriate, providing good ventilation for components, setting speaker delays and calibrating channel levels, calibrating TV using discs like Digital Video Essentials, etc), there are some products and concerns that I would classify as "nonsense" - and keeping speaker cables off the floor is one of those. What would contact with the floor actually do to the signal in the cable? Are we worried about friction against one side of the audio signal? Don't worry about that one...