All this concern about cables pales into insignificance when compared to the effect atmospheric pressure has on speakers.
You can have the best coloured cable but if the air pressure in the atmosphere is high then your speaker won't be able to move fast enough to make those high frequencies clear anyway.
Ever had those days when your amp just sounds a bit muffled but you can't put your finger on why? You can bet it'll be a hot sunny day with high atmospheric pressure.
It has less of an effect on ported cabs as the pressure is equalised quicker, sealed cabs can be a nightmare.
It's for this reason that most outdoor festival stages are set up facing downwind, the event organisers are obviously hoping for good weather, which will usually be a result of high pressure, so the 'high atmospheric pressure driver unit slowing effect', as it's known, is counteracted by having the prevailing wind blowing from the stage towards the crowd, thus encouraging the driver units forwards by creating a tiny area of low pressure in front of the cabinets.
Ditch this cable colour bull and keep an eye on the weather.