My certifications are no longer current. I was an ASE Master Automobile tech, asking with L1 and a handful of truck and body certs. My specialty was electrical and computer controls in General Motors cars and light trucks.
Pretty much everything I worked on was low switched. Fuel pumps and PCMs were the only notable exceptions.
The primary reason I like using this method is simplicity. With a fuse at the battery, any short before the load opens the circuit, and any short after activates the load. Diagnostics are simplified in that regard. Further, there is only one wire going to the load, allowing the ground relay to be located as near to whatever ground pack is available.
Also, the live site can be sized up for future expansion. It just makes everything easier.
I only use fast reacting blade type fuses in my circuits. Any short I've experienced prior to the load has resulted in an instant open, generally accompanied with an audible "POP!".
Since we both have spent a good amount of time here, something I understood but failed to state was mechanical protection and some equipment still comes with a grounded to casting circuit, I would say 98% of all led lighting comes with a positive and negative wire ( no common negative ground to casting ), which allows this to be connected anywhere in the world, and many come able to work from 9 to 32 VDC.
Kawasaki has a fused live at all times circuit that goes to power the optional Aux. relay circuit. In the automotive industry, the advantage of positive to devices and switching grounds, as a example the door switches, you can have 100 door switches all turning on the same light, the fun begins when the light doesn't turn off, however todays cars have door open indicators , truthfully the electronics / wiring is getting very complex such as Canbus wiring, Admore Lighting offers some add on lighting capable of using Canbus.
So my only concern was mechanical protection to what I would call exposed wiring at those fog lights, I failed to explain that.
Thanks for explaining automotive electrical trouble shooting.
In my industrial setting, many times control voltage was 120 VAC , and many times stand alone combination magnetic starter would have their own control transformer transformed down to 120 VAC, one side would be fused and what was referred to as the neutral was to be grounded, many times this wasn't done nor was a fuse added to the ungrounded circuit, what a PITA trying to trace a open circuit. Also very dangerous , typically with a grounded neutral , you could go to multiple E stops and using a meter go from the normally closed contact terminals to ground, eventually you would find no or drastically reduced VAC . So ground reference is highly used in inverter circuits, most power supplies are plus and minus 24 VDC , when you see a WRTG on a drawing ( with respect to ground) .