Help Me Explain Power Cables to my Guitar Friends

Guys, I need some help!

I have suggested to some of my guitar geek buddies that they could improve the performance of their tube guitar amps by replacing the power cords. Now, I know that many here already believe in the qualities of upgraded power cords. But I can't convince my guitar buddies; they won't even try it because they say, "You need to show me some scope measuresments before I believe this 'snake oil' stuff about power cords."

Does anybody know of some way you can "measure" power cords that would "demonstrate" that they can improve performance? Help me out here!
If the power supply and power cord in your friends guitar amplifier is appropriately designed and sized then I am afraid your friends are most probably right.
Cool thread. It is pretty funny as I would think your friends would be open to to this. I play the guitar (or at least I try to) but I have two friends in a band who are very serious about their "tone" as it makes them unique sounding.

They have actually re-wired a lot of their gear with Audience and Audioquest wire, and done other improvments. They also insist on running choice NOS tubes in their amps.

I recently saw DADA live in Falls Church, VA and I have never heard a Fender Strat sound like Mike Gurley's.It was absolutely amazing! I talked to a friend of mine who has actually played with him and he as gone to great extremes (Nos Tubes, Re-Wiring, Effects) to get that sound. Not to mention, he will not share his setup with anyone.

Even Audience now offers guitar cables which I have yet to try but they are now on their website. I guess it depends on being open minded and willing to experiment..

Thanks for the responses, all! Here's the rub with the guitar guys: Many of them are just plain prejudice when it comes to audiphilia. Unfortuantely, it's just an attitude problem. What's surprising is how vitriolic the responses are to a suggestion of, say, a power cord for an amp. They just dismiss it as nonsense! It's sad, but more than just a few guitar guys can really be a bunch of flat-earthers. Oh well . . . For the record, I'm playing a Dr Z Maz 18 Jr, which is basically the audiophile version of a guitar amp. I play G&L ASATs mostly.
Crazy4Blues, I'd have to agree with the_kid - guitarists are all over the map when it comes to this stuff. Since you play guitar, I am sure you have heard of Eric Johnson. He is known for going to extremes that would make even the tweakiest audiophiles blush - spending days trying to hear which battery sounds best in an effects pedal, etc... I have to admit I fell for the whole cryo'd string thing back in the early 90's.