And often the wire will fail due to the flux, even the non corrosive resin.
When the solder wicks under the insulation it makes the wire brittle, which is the reason for the aircraft qualified crimps.
Nothing wrong with soldering, but I could not make an aircraft connection "mid air" anyway.
The skin effect of current traveling along the surface is more at high frequencies and definitely not DC.
I still think that using two conductor cable to put two colors in one vinyl cover keeps everything neat and a single run to each load takes care of the other.
I broke my lighting
up ointo several runs so that one blown fuse would not put me in the dark.
The PD4045 I used had plenty of fused circuits and I brought each wire from the converter to a terminal strip numbered in the same order as the fuses on the front panel
Here is a picture before I neatened up the wiring. The grounds go the the buss bars on the "new " steel wheel wells.