The ad for the Norge washer, gas dryer and gas water heater has the statement that the gas water heater could keep up with the washday demands for hot water. It is interesting to note that Norge washers, except for the most deluxe, paired a hot wash with a cold rinse in the preset water temperature selections. The user could wait until the hot fill was complete to turn the selector to warm wash & warm rinse to override this, but the setting which used the most hot water, hot wash and warm rinse was not automatically available on most models. Like many solid tub washers, Norge used an overflow rinse which would have further increased the demand, by a few gallons, for hot water with a warm rinse. It's not a big deal and I am sure that the water heater performed well.
Actually, if not for the electric power companies' rules, domestic electric water heaters could be as fast as gas water heaters. For domestic electric water heaters, the upper and lower elements are not wired to operate simultaneously because of the huge demand for power that would create and the necessity for heavier lines, larger transformer substations and greater generating capacity. Commercial electric water heaters can be filled with elements that can operate in any number at the same time to keep up with the demand, but different rules and rates apply.