Interconnect Cable Current Flow Direction

Regarding interconnect cables without direction arrows:
I consider the labelled or banded end of an interconnect cable to be the source end. Is this the generally accepted norm? Some cables are just plain. But when you purchase cables with a band or label at one end, often this means something, but they rarely tell you what. Somewhere along the way I think someone told me that this is the source end. Thank you!
If the cable has no directional arrow it does not matter how you hook it up. Just don't change the direction once it is connected
The laws of physics don't change just to suit the whim of a few cable manufacturers. All metal wires are directional as regards sound quality. One need look no further than the proliferation of aftermarket fuses with little direction arrows on them to realize that all wires, no matter how small, are directional. Put them in one way and they sound relatively anemic, weird, rolled off, bass shy, lacking in detail. Put them in the other way and they sound full, coherent, extended, propulsive, dynamic and natural.