Stehno - The point made was that aftermarket power cords can produce a significant improvement in a system regardless of what type of conductor (romex or home depot power cord) precedes it.
From your post I get the impression that you do not believe this and have yet to be too impressed with aftermarket powercords in general. I might suggest that you actually try a few good high end aftermarket power cords before you start comparing them to zip cord. This will add credibility to your posts since your oppinion is clearly based on experiences that differ from those of the greater majority. I usually associate comments such as those you've made with a person who tried a cheap aftermarket cord and was dissatisfied with the results.
However, I must say you are partially correct, in some cases, cheap aftermarket cords are not much better than stock or zip cords.
Given that GOOD aftermarket powercords (such as Purist Audio's Dominus) truly DO make a difference we pondered the idea of replacing the romex entirely with an longer version of the power cord. OF course this was purly fantasy since few people have the means to complete such a project and its doubtful that electrical code would allow a power cord to be run from circuit breaker to a component.
Thanks for your help in getting this thread back on track!