From the more is better school of thought. Just tell him to read the Zaino directions on the bottle or the web site. Even a carnuba user doesn't apply 3-4 oz of wax per coat. It must take forever for this amount to ever dry. I doubt if he is applying this much because if so he would have become frustrated with the smearing and thrown the Zaino in the trash. Or maybe he was the guy with the truck that RedCarGuy saw that was in a mall parking lot with wax still on his car.

If following the Zaino directions is an issue, just tell him very, very, very thin coats will do the job. No special tricks or tips are necessary... just thin coats. He'll probably be surprise of what he has been missing.
