LM,
Do you mean to say that because they have selected a well respected (already expensive) cable like Monster and chosen to make it go head to head with a $7,000 cable that it would be hard to tell the difference? If so, then I guess you agree with the general idea that "extraordinary" differences (the kind of claims made by many cable manufacturers and supported by reviewers) would not stand up to any serious test.
If you are suggesting that the challengers allow a 12 AWG wire to go up against a 30 AWG wire then no doubt the effect would be quite clearly audible (a million dollars would be quickly gone); deliberate selection of extreme cable resistance differences is bound to be audible due to the SPL drop. Similarly, if one were to select a cable with some active elements (capacitor/inductor) then the roll-off effect might become quite audible in some cases.
Dave,
Yes indeed a good start. You may be able to save me yet! What wire would you suggest for the mains?