Dave, I don't know what the A'gon discussion was about, but I would take the charts in that link with a grain of salt. The article tries to calculate the gauge of power wire required as a function of amplifier output wattage. I just don't think that this is a valid linkage frt several reasons.
First, required gauge of power cable is a function of the input amperage, not the power output of the amp. using power output as the yardstick completely ignores what type of amplifier you are looking at . In general a Tube amp will draw more power than a solid state amp of similar output power and in addition to the the Tube vs SS differences Class A amp design is much less efficient than a class D amp and as such will draw more power. Given this is it not really possible to make a direct correlation between output wattage and the required input power of an amplifier.
Secondly the article is talking about car stereos ans because of power, space and heat considerations is is most likely that the amplifiers used in a car would overwhelmingly be Class D, which is not the case for home audio.
Lastly and perhaps most importantly, home audio is powered by 120v AC whereas car amps would be run on 12 to 14 volt DC. the lower voltage of the car audio DC systems would require in the area of an order of magnitude more amperage to provide the same input power to an amp when compared to a 120v fed system. Thus I don't think the wire gauges this guy recommends for a car stereo amp can be used as a guide for what is needed in your home system.
All that said, if I take off my engineering hat and put on my audiophile one, form a real world perspective I have done quite a bit of auditioning of Pete's Triode Wire Labs power cords over the years and I have to say that on my Mac 275 his 7ga cables sound significantly better that the 10 ga versions. According to the chart in that link my 75wpc stereo amp should be using 10ga power cable. So not withstanding my engineers thoughts on why the chart is not really applicable to home stereo systems, my real world experience contradicts its findings as well.
As Pete always says, Just my 2 cents........