Verified answer

You aren't running delay off of a toggle. It uses a timer circuit to set the delay times. You will need some sort of timer circuit to do that no matter how you cut it. Absolutely pointless, a rheostat/potentiometer type (just like stock) is the best compromise and easiest way to accomplish delay.

Edit: To clarify, the wipers always use 12V, otherwise wiper arm speed would decrease as frequency decreased, which is bad. This is unlike the heater, where the resistor pack decreases the actual voltage to the heater blower motor. The delay module (or PCM/BCM depending on vehicle) only changes the frequency of when the wiper motor is triggered to wipe.