As with speaker wires I thought like most of the people on this message board. An insulated zip cord is still a zip cord. But I think Scott picked one really seemingly 'special' zip cord. Try out the Kimber 4TC. If you bi-wire 4TC on top with 8TC on bottom and you will notice something with this special type of zip cord.
I tried Monster MCX and the Monster Z2 reference. Some people have mentioned that those are crappy compared to the Kimbers.

http://www.kimber.com

http://www.hifichoice.co.uk/review_read.asp?ID=419

http://www.audioreview.com/Cables/Kimber,Kable,8TC/PRD_116464_1584crx.aspx

http://www.audioreview.com/Cables/Kimber,Kable,4TC/PRD_116461_1584crx.aspx



http://www.quadloft.com/hometheater- new HT