Patchworks can never be considered true hairless as true hairless is a recessive trait completely different than the Dominate rex trait that a double rex patchwork is.
I don't have pics but one of my partners has several almost completely naked double rex moms that have no problems nursing their young.
He can also get his hairless moms to feed 2 or 3 kits but that's about it, they do lactate but not enough to feed a whole litter so he passes the babies out to other moms.
I've gone away from double rex's except in my dwarf lines but I will say some of the nicest rex coats I've made have come from double rex to standard coat.