The power for a typical residential house starts at the utility power transformer, that is after all a split phase isolation transformer. Or as some call balanced power....
A power cord is an extension of the leads of the primary winding of the power transformer of a piece of audio equipment. And is not the last few feet of a branch circuit.
For you naysayer you might want to do some research on the subject.
Just to name three names....
The late Robert Crump. Audio equipment designer, and....
Jon Risch. A well known and respected EE.
The late Al Sekela. A well known and respected EE.
>http://forum.audiogon.com/cgi-bin/fr.pl?fcabl&1266057510&openfrom&1&4#1