Rabbi is saying that because every detailer has different tastes. Some will like one look while others will hate the same thing. In trying each method out on a different part of the car you end up getting a side-by-side comparison of each combination, you can then review things like gloss, depth, ease of use, durability, and whatever else you look for in a wax. Such comparisons are the way that you can develop an eye for what works, what doesn't work, and what your personal preferences are. When a tire manufacturer is developing a new tire, they will buy several sets each of the competitor's tires to see what to improve upon, using different processes and combinations in detailing acomplishes the same goal. I would highly suggest following rabbi's advise, you will undoubtedly find a combination that suits both your needs and desires.