By "what's worked for me" do you mean it fixed the dimming issue 100%? Or did it improve it markedly?
It corrected a lot of issues. My VDC came from Boston. A lot is rust at ground lugs, undercarriage bolts, etc.. One of the first things I did was clean up every ground in the engine compartment. The conductivity measured excellent only losing 50 amps between the battery and block and 75 between the battery and firewall. Dimming went away. I added in the 4 ga and it improved to a 40 amp loss to the body. This also helped a great deal when I overhauled the sound system.
Any time you reduce electrical flow loss, its an improvement. Corrosion is an inhibitor. Silicates are inhibitors. Loose connections. But you also have to have a good source and that is the battery.
Upon installing the SC, I added more grounding to handle the loads I created with added sensors, gauges and the 2 cooler pumps. I also now use a deep cell battery.