I've used a similar method where I spray the car off at the local pay 'n spray to get any dirt and gunk off the car. Take it home park it in the garage then heavily pre-soak the entire car with diluted rinseless. Afterwards, I start the entire rinseless wash never drying the car until car is completely rinseless washed. Haven't had any dry spots and if any arise while doing the wash, I just take the Kwazar Venus sprayer and mist the diluted rinseless on that part of the car. After drying the car, I'll sometimes do panel by panel with detail spray just for an added glossy finish. Works great and seems to speed the process up a little more.