[aussie merc]

as time progressed so did the expectations of motorists and hence electrical loads and requirements. Early cars with hand crank start acetylene lamps and magnetos so no wiring or battery . We progress and expect more for less i can remember having cars in the late 80s that still only had 2 factory fuses i ended up splitting circuits because 1 short would literally stop the whole motor vehicle Hence manufacturers also began splitting circuits till we get to todays times of 30 plus fuses in several banks .So if there is a problem in say the power windows the wipers will still work [byproduct makes fault finding a lot quicker as it isolates the fault not 1/2 the car ] also in efforts to save money manufactures are useing less wire so circuits can carry less current without damage. So in my opinon always fuse !!