Do speaker cables need a burn in period?

@teo_audio  Well, if that were the case i would had trouble staying employed for the last 40 years.  

So reading your response you are trying to say that in some cases 
AC current does NOT behave in the way science & engineers understand it? 

Your statement sounds like the definition of Pseudoscience which consists of statements, beliefs, or practices that are claimed to be both scientific and factual, but are incompatible with the scientific method.

Az, it’s OK that you were lying about being an engineer. I totally understand why you would do that.  You must be the oldest Subway employee on the planet.

I can see the argument for "directionality" if the condition is not symmetric.
Let's say if one end of the cable is subjected to one condition, and the other
end is subjected to different condition, then it's possible that the cable
could be conditioned differently if you reverse the direction. For example,
if one end is constantly biased to one voltage, and another end is biased
to another voltage, then there is a possibility that the argument for "direction" has some merrits. No if the current is DC then of course you have directionality, no question about it. But music signal is AC so that is the tricky part to argue if you are the proponent of "directionality".
But if the current is truely AC, then the current is always symmetric.
But is the currrent always AC? Could there be a small DC offset current?

For example, you have an amp driving a speaker, one terminal of the cable is being biased by the amp output transistors and the other terminal of the cable is connected to the speakers. If the output transistors are DC coupled, then you have a servo on the amp output to adjust for the DC offset, but this servo circuit does have a small (maybe even very small)DC offset so there will be  a small net DC current flowing from the amp to the speaker. So in this case,  it's not symmetric and the "directionality" argument might make sense.

In the case of interconnect, you have a preamp driving the amp input. In
this case, DC offset is not as important because you don't have anything
driving the speakers. I am not a preamp or amp designer so I don't know
how the detail of the preamp output design or the amp input design, but
there is a strong possibility that the interconnect terminals on both ends
are not being subjected to the same condition, so therefore there is an
argument for "directionality" even if the current is always AC (for example
the preamp output is capacitively "coupled" to the cable but the amp
input is biased to some voltage). So in this case, you have a symmetric
AC current, but non-symmetric bias condition on the terminals of the interconnect.

For the proponents of "directionality", the difficult part is that you have to
make a case how a symmetric AC current has anything to do with "directionality".

For the opponent of "directionality", you have to explain how different
bias condition on the terminals of the cable does not affect the cable
if you reverse the cable direction.

I am not a proponent or opponent of "directionality" but I present some
possibilities for the "directionality" argument.

@geoffkait 

Ok now you are lowering the conversation to insults, pretty low grade insults too which is just another way you are avoiding the very simple request to document your claims, is wire directional, and HOW would that work in a AC circuit??

@andy2  audio interconnections and amp to speaker connections are AC, there is no DC involved in these connections.  There IS DC internal to pre-amps & amps, its what their power supplies are there for to convert AC power from the wall to pure DC, voltages depend on the design & function of these components.

Another case for the "directionality" people, is that even if both ends
are not being bias differently and the current is truely AC, on the driving
terminal in this case is the amp, the voltage is always slightly higher
than the other end since there is always some resistive losses in the cable.
Think of the cable as a simple voltage divider driving the speakers as a load. You have input voltage and output voltage. Obviously for a voltage divider, the output voltage is always smaller than the input voltage. So at least in this case, you have "directionality" because the one terminal is subjected to one voltage and another terminal is subjected to another voltage.

What I said above is just theoretical. In practical situation, I have to
admit it would be different to hear the difference unless I guess have
have a really exceptional system with top notch transparency.