I'm new, and maybe naive, so forgive me if I'm wrong. But cable length is not a matter of the 186,000 miles a second, so much as a matter of the load of resistance.
Electrical resistance increases with the length of the conductor. And it decreases with a greater diameter of conducter. If one speaker cable is a LOT longer than the other, then the resistance is going to be different between the two speakers, resulting in different performance in each channel. The longer cable robs power from the signal in the form of resistance. The power available to that speaker is diminished by the added resistance. And we know it's better to have both speakers sound the same. It's better to have both speakers running at, say a dimished "98%" (both cables REALLY long), than to have one at 98% (with a REALLY long cable) and one at 100% (REALLY short).
This effect will be much more significant with small diameter cables.
Electrical resistance increases with the length of the conductor. And it decreases with a greater diameter of conducter. If one speaker cable is a LOT longer than the other, then the resistance is going to be different between the two speakers, resulting in different performance in each channel. The longer cable robs power from the signal in the form of resistance. The power available to that speaker is diminished by the added resistance. And we know it's better to have both speakers sound the same. It's better to have both speakers running at, say a dimished "98%" (both cables REALLY long), than to have one at 98% (with a REALLY long cable) and one at 100% (REALLY short).
This effect will be much more significant with small diameter cables.