Power cord for low-watt tube amp?

by those whose systems are not resolving enough to show the audible differences in cable

Have you determined that these people even have systems? I don't see any evidence that they do.

Mechans, some people make reasoned arguments and allow for differing opinions, while others spout dogma based upon absolute "truths". I only wonder about the systems of the latter people.

My own observation is that power cords are very component sensitive, but can make a worthwhile, if still subtle, sonic difference. I think power cords are worth experimenting with, but I'm not convinced someone should spend large amounts of money on them. But if you do jump into PCs with both feet, then also upgrade your wall sockets and your components IEC inlets. You might even want to eliminate the inlet and go hard wire. I refuse to even consider whether the outlet socket cover has a sonic effect.