It was mentioned to run a smaller ground wire as a "fuse". Why not just go to NAPA and buy a 100 amp ( I think that is what I have in, but not sure.) fuse and put that in the positive cable right at the battery. Much safer than relying on a homemade "fusible link".
Starters can pull more than 100 amps. It's not about fusing the auxiliary systems it's about protecting the main power wire to the starter. I have had the starter come loose and when I went to start the car that is when all heck broke loose. Factory trunk mounted cars use a similar method or use non burn wiring covers(like a fusible link has) to prevent the car from burning if the main trunk line gets shorted.
Like you pointed out though. Auxiliary systems should always be fused with a fuse or fusible link.
