i think you are right gonk(i'm not gonna pretend to "know something" if i'm not sure)
but i'm doing it all for reserve in my truck i have an 160 amp alternator that cannot power the truck and stereo so, basically they provide the ooooooommmph for a peak (reserve)i was sold on my amps because the are "unregulated" whereas if you can put more in you get more out (to a limit of course)